Hi again @theuntergeek,
I followed your advice and I definitely got more info by setting the log level to DEBUG.
I think we're pretty close to a solution. This is what I see from the logs.
The curator selects all the indices:
...
Generating working list of indices
2020-06-19 17:06:56,898 DEBUG          curator.indexlist     iterate_over_stats:126  Index: cloudtrail-2020.05.13  Size: 7.4GB  Docs: 37510
2020-06-19 17:06:56,898 DEBUG          curator.indexlist     iterate_over_stats:126  Index: cloudtrail-2020.05.12  Size: 15.8GB  Docs: 79355
2020-06-19 17:06:56,898 DEBUG          curator.indexlist     iterate_over_stats:126  Index: cloudtrail-2020.05.11  Size: 4.1GB  Docs: 25720
2020-06-19 17:06:56,898 DEBUG          curator.indexlist     iterate_over_stats:126  Index: cloudtrail-2020.05.10  Size: 73.4MB  Docs: 6257
2020-06-19 17:06:56,898 DEBUG          curator.indexlist     iterate_over_stats:126  Index: metricbeat-7.5.0-2020.04.15-000004  Size: 276.9MB  Docs: 913723
2020-06-19 17:06:56,898 DEBUG          curator.indexlist     iterate_over_stats:126  Index: .kibana_task_manager_1  Size: 27.9KB  Docs: 2
2020-06-19 17:06:56,898 DEBUG          curator.indexlist     iterate_over_stats:126  Index: .monitoring-es-7-2020.06.13  Size: 616.3MB  Docs: 1868761
2020-06-19 17:06:56,899 DEBUG          curator.indexlist     iterate_over_stats:126  Index: .monitoring-es-7-2020.06.14  Size: 444.4MB  Docs: 1344214
2020-06-19 17:06:56,899 DEBUG          curator.indexlist     iterate_over_stats:126  Index: .monitoring-es-7-2020.06.15  Size: 622.3MB  Docs: 1885249
2020-06-19 17:06:56,899 DEBUG          curator.indexlist     iterate_over_stats:126  Index: .monitoring-es-7-2020.06.16  Size: 624.2MB  Docs: 1894112
2020-06-19 17:06:56,899 DEBUG          curator.indexlist     iterate_over_stats:126  Index: .monitoring-es-7-2020.06.17  Size: 444.0MB  Docs: 1265658
2020-06-19 17:06:56,899 DEBUG          curator.indexlist     iterate_over_stats:126  Index: .monitoring-es-7-2020.06.18  Size: 398.5MB  Docs: 969073
2020-06-19 17:06:56,899 DEBUG          curator.indexlist     iterate_over_stats:126  Index: .monitoring-es-7-2020.06.19  Size: 543.0MB  Docs: 678946
2020-06-19 17:06:56,899 DEBUG          curator.indexlist     iterate_over_stats:126  Index: .monitoring-kibana-7-2020.06.14  Size: 1.3MB  Docs: 6173
2020-06-19 17:06:56,899 DEBUG          curator.indexlist     iterate_over_stats:126  Index: .monitoring-kibana-7-2020.06.13  Size: 1.9MB  Docs: 8635
2020-06-19 17:06:56,899 DEBUG          curator.indexlist     iterate_over_stats:126  Index: .monitoring-kibana-7-2020.06.16  Size: 1.9MB  Docs: 8639
2020-06-19 17:06:56,899 DEBUG          curator.indexlist     iterate_over_stats:126  Index: .monitoring-kibana-7-2020.06.15  Size: 1.9MB  Docs: 8639
2020-06-19 17:06:56,899 DEBUG          curator.indexlist     iterate_over_stats:126  Index: metricbeat-7.5.0-2020.04.08-000003  Size: 271.8MB  Docs: 899106
...
It applies the regex and age filters:
...
Filtering indices by regex
2020-06-19 17:06:56,908 DEBUG          curator.indexlist       empty_list_check:226  Checking for empty list
2020-06-19 17:06:56,908 DEBUG          curator.indexlist           working_list:237  Generating working list of indices
2020-06-19 17:06:56,908 DEBUG          curator.indexlist        filter_by_regex:451  Filter by regex: Index: logstash-2020.05.25
2020-06-19 17:06:56,908 DEBUG          curator.indexlist       __not_actionable:39   Index logstash-2020.05.25 is not actionable, removing from list.
2020-06-19 17:06:56,908 DEBUG          curator.indexlist        filter_by_regex:451  Filter by regex: Index: cloudtrail-2020.04.26
2020-06-19 17:06:56,908 DEBUG          curator.indexlist           __actionable:35   Index cloudtrail-2020.04.26 is actionable and remains in the list.
2020-06-19 17:06:56,909 DEBUG          curator.indexlist        filter_by_regex:451  Filter by regex: Index: logstash-2020.06.13
2020-06-19 17:06:56,909 DEBUG          curator.indexlist       __not_actionable:39   Index logstash-2020.06.13 is not actionable, removing from list.
2020-06-19 17:06:56,909 DEBUG          curator.indexlist        filter_by_regex:451  Filter by regex: Index: logstash-2020.06.15
2020-06-19 17:06:56,909 DEBUG          curator.indexlist       __not_actionable:39   Index logstash-2020.06.15 is not actionable, removing from list.
2020-06-19 17:06:56,909 DEBUG          curator.indexlist        filter_by_regex:451  Filter by regex: Index: cloudtrail-2020.04.18
2020-06-19 17:06:56,909 DEBUG          curator.indexlist           __actionable:35   Index cloudtrail-2020.04.18 is actionable and remains in the list.
2020-06-19 17:06:56,909 DEBUG          curator.indexlist        filter_by_regex:451  Filter by regex: Index: cloudtrail-2020.04.25
2020-06-19 17:06:56,909 DEBUG          curator.indexlist           __actionable:35   Index cloudtrail-2020.04.25 is actionable and remains in the list.
2020-06-19 17:06:56,909 DEBUG          curator.indexlist        filter_by_regex:451  Filter by regex: Index: cloudtrail-2020.04.20
2020-06-19 17:06:56,909 DEBUG          curator.indexlist           __actionable:35   Index cloudtrail-2020.04.20 is actionable and remains in the list.
2020-06-19 17:06:56,909 DEBUG          curator.indexlist        filter_by_regex:451  Filter by regex: Index: cloudtrail-2020.04.01
2020-06-19 17:06:56,909 DEBUG          curator.indexlist           __actionable:35   Index cloudtrail-2020.04.01 is actionable and remains in the list.
2020-06-19 17:06:56,909 DEBUG          curator.indexlist        filter_by_regex:451  Filter by regex: Index: logstash-2020.06.12
...
Filtering indices by age
2020-06-19 17:06:56,923 DEBUG          curator.indexlist   _get_name_based_ages:280  Getting ages of indices by "name"
2020-06-19 17:06:56,923 DEBUG          curator.indexlist       empty_list_check:226  Checking for empty list
2020-06-19 17:06:56,923 DEBUG              curator.utils         get_date_regex:200  regex = \d{4}\.\d{2}\.\d{2}
2020-06-19 17:06:56,924 DEBUG          curator.indexlist           working_list:237  Generating working list of indices
2020-06-19 17:06:56,929 DEBUG          curator.indexlist           working_list:237  Generating working list of indices
2020-06-19 17:06:56,929 DEBUG          curator.indexlist           __actionable:35   Index cloudtrail-2020.04.26 is actionable and remains in the list.
2020-06-19 17:06:56,929 DEBUG          curator.indexlist            __excludify:58   Remains in actionable list: Index "cloudtrail-2020.04.26" age (1587859200), direction: "older", point of reference, (1589994416)
2020-06-19 17:06:56,929 DEBUG          curator.indexlist           __actionable:35   Index cloudtrail-2020.04.18 is actionable and remains in the list.
2020-06-19 17:06:56,929 DEBUG          curator.indexlist            __excludify:58   Remains in actionable list: Index "cloudtrail-2020.04.18" age (1587168000), direction: "older", point of reference, (1589994416)
2020-06-19 17:06:56,929 DEBUG          curator.indexlist           __actionable:35   Index cloudtrail-2020.04.25 is actionable and remains in the list.
2020-06-19 17:06:56,930 DEBUG          curator.indexlist            __excludify:58   Remains in actionable list: Index "cloudtrail-2020.04.25" age (1587772800), direction: "older", point of reference, (1589994416)
2020-06-19 17:06:56,930 DEBUG          curator.indexlist           __actionable:35   Index cloudtrail-2020.04.20 is actionable and remains in the list.
2020-06-19 17:06:56,930 DEBUG          curator.indexlist            __excludify:58   Remains in actionable list: Index "cloudtrail-2020.04.20" age (1587340800), direction: "older", point of reference, (1589994416)
2020-06-19 17:06:56,930 DEBUG          curator.indexlist           __actionable:35   Index cloudtrail-2020.04.01 is actionable and remains in the list.
2020-06-19 17:06:56,930 DEBUG          curator.indexlist            __excludify:58   Remains in actionable list: Index "cloudtrail-2020.04.01" age (1585699200), direction: "older", point of reference, (1589994416)
2020-06-19 17:06:56,930 DEBUG          curator.indexlist           __actionable:35   Index cloudtrail-2020.04.06 is actionable and remains in the list.
2020-06-19 17:06:56,930 DEBUG          curator.indexlist            __excludify:58   Remains in actionable list: Index "cloudtrail-2020.04.06" age (1586131200), direction: "older", point of reference, (1589994416)
2020-06-19 17:06:56,930 DEBUG          curator.indexlist           __actionable:35   Index cloudtrail-2020.03.31 is actionable and remains in the list.
2020-06-19 17:06:56,930 DEBUG          curator.indexlist            __excludify:58   Remains in actionable list: Index "cloudtrail-2020.03.31" age (1585612800), direction: "older", point of reference, (1589994416)
2020-06-19 17:06:56,930 DEBUG          curator.indexlist           __actionable:35   Index cloudtrail-2020.04.12 is actionable and remains in the list.
2020-06-19 17:06:56,930 DEBUG          curator.indexlist            __excludify:58   Remains in actionable list: Index "cloudtrail-2020.04.12" age (1586649600), direction: "older", point of reference, (1589994416)
What I don't get is the last bit, where it seems there's another filter that eventually removes all the "cloudtrail"-related indices:
Filtering indices with index.lifecycle.name
2020-06-19 17:06:56,950 DEBUG          curator.indexlist       __not_actionable:39   Index cloudtrail-2020.03.28 is not actionable, removing from list.
2020-06-19 17:06:56,950 DEBUG          curator.indexlist            __excludify:58   Removed from actionable list: cloudtrail-2020.03.28 has index.lifecycle.name cloudtrail
2020-06-19 17:06:56,951 DEBUG          curator.indexlist       __not_actionable:39   Index cloudtrail-2020.04.24 is not actionable, removing from list.
2020-06-19 17:06:56,951 DEBUG          curator.indexlist            __excludify:58   Removed from actionable list: cloudtrail-2020.04.24 has index.lifecycle.name cloudtrail
2020-06-19 17:06:56,951 DEBUG          curator.indexlist       __not_actionable:39   Index cloudtrail-2020.05.13 is not actionable, removing from list.
2020-06-19 17:06:56,951 DEBUG          curator.indexlist            __excludify:58   Removed from actionable list: cloudtrail-2020.05.13 has index.lifecycle.name cloudtrail
2020-06-19 17:06:56,951 DEBUG          curator.indexlist       __not_actionable:39   Index cloudtrail-2020.05.12 is not actionable, removing from list.
2020-06-19 17:06:56,951 DEBUG          curator.indexlist            __excludify:58   Removed from actionable list: cloudtrail-2020.05.12 has index.lifecycle.name cloudtrail
2020-06-19 17:06:56,951 DEBUG          curator.indexlist       __not_actionable:39   Index cloudtrail-2020.05.04 is not actionable, removing from list.
2020-06-19 17:06:56,951 DEBUG          curator.indexlist            __excludify:58   Removed from actionable list: cloudtrail-2020.05.04 has index.lifecycle.name cloudtrail
2020-06-19 17:06:56,951 DEBUG          curator.indexlist       __not_actionable:39   Index cloudtrail-2020.04.06 is not actionable, removing from list.
2020-06-19 17:06:56,951 DEBUG          curator.indexlist            __excludify:58   Removed from actionable list: cloudtrail-2020.04.06 has index.lifecycle.name cloudtrail
2020-06-19 17:06:56,951 DEBUG          curator.indexlist       __not_actionable:39   Index cloudtrail-2020.04.22 is not actionable, removing from list.
2020-06-19 17:06:56,951 DEBUG          curator.indexlist            __excludify:58   Removed from actionable list: cloudtrail-2020.04.22 has index.lifecycle.name cloudtrail
2020-06-19 17:06:56,951 DEBUG          curator.indexlist       __not_actionable:39   Index cloudtrail-2020.04.28 is not actionable, removing from list.
2020-06-19 17:06:56,951 DEBUG          curator.indexlist            __excludify:58   Removed from actionable list: cloudtrail-2020.04.28 has index.lifecycle.name cloudtrail
2020-06-19 17:06:56,951 DEBUG          curator.indexlist       __not_actionable:39   Index cloudtrail-2020.04.26 is not actionable, removing from list.
2020-06-19 17:06:56,951 DEBUG          curator.indexlist            __excludify:58   Removed from actionable list: cloudtrail-2020.04.26 has index.lifecycle.name cloudtrail
Could you let me know what that last filter is about and how I can make the indices pass it?
BTW, I took the "cloudtrail" index as an example but it happens with all the other ones except for "logstash".
Let me know if you need any more info.
Thanks a lot,
Alex