Kibana won't start up after upgrading to 7.2.0

Hi,
I'm having trouble starting up kibana after upgrading to 7.2.0;
It is throwing following logs:

    {"type":"log","@timestamp":"2019-07-18T07:39:48Z","tags":["reporting","debug"],"pid":15699,"message":"Running on os \"linux\", distribution \"Ubuntu Linux\", release \"18.04\""}
{"type":"log","@timestamp":"2019-07-18T07:39:48Z","tags":["debug","task_manager"],"pid":15699,"message":"Not installing .kibana_task_manager index template: version 7020099 already exists."}
{"type":"log","@timestamp":"2019-07-18T07:39:48Z","tags":["debug","task_manager"],"pid":15699,"message":"Not installing .kibana_task_manager index template: version 7020099 already exists."}
{"type":"log","@timestamp":"2019-07-18T07:39:48Z","tags":["reporting","debug"],"pid":15699,"message":"Reporting plugin self-check ok!"}
{"type":"log","@timestamp":"2019-07-18T07:39:48Z","tags":["debug","task_manager"],"pid":15699,"message":"Not installing .kibana_task_manager index template: version 7020099 already exists."}
{"type":"log","@timestamp":"2019-07-18T07:39:48Z","tags":["debug","task_manager"],"pid":15699,"message":"Running task vis_telemetry \"oss_telemetry-vis_telemetry\""}
{"type":"log","@timestamp":"2019-07-18T07:39:48Z","tags":["warning","task_manager"],"pid":15699,"message":"Task vis_telemetry \"oss_telemetry-vis_telemetry\" failed in attempt to run: [version_conflict_engine_exception] [oss_telemetry-vis_telemetry]: version conflict, required seqNo [11977], primary term [10]. current document has seqNo [11978] and primary term [10], with { index_uuid=\"v8PvZUHmQdq71qSoV-84LQ\" & shard=\"0\" & index=\".kibana_task_manager\" }"}
{"type":"log","@timestamp":"2019-07-18T07:39:48Z","tags":["info","migrations"],"pid":15699,"message":"Creating index .kibana_3."}
{"type":"log","@timestamp":"2019-07-18T07:39:48Z","tags":["debug","upgrade_assistant","reindex_worker"],"pid":15699,"message":"Could not fetch riendex operations from Elasticsearch"}
{"type":"log","@timestamp":"2019-07-18T07:39:48Z","tags":["debug","root"],"pid":15699,"message":"shutting root down"}

And cycles itself every few seconds / minutes. Only warnings / errors I see there are the ones about Task manager with version conflict and missing reindex operations from Elasticsearch (is that an issue?).

any ideas what could be causing it? ES seems to be running and in healthy state.

ok, got it fixed.
After all it was ES related; hard shards quota set to 1000.

Did run:
curl -XPUT -H 'Content-Type: application/json' '127.0.0.1:9200/_cluster/settings' -d '{ "persistent" : {"cluster.max_shards_per_node" : 2000}}'

and now everything runs well. Just need to lower down my shards there...