How to manage different timezone

Hi,
I'm uploading IoT data via logstash to elasticsearch. The data comes from machines that have a datetime with different time zones. I realized that the time is changed by the local timezone (the time is moved forward by 1 hours wherever they come from). I tried to put UTC in the advanced settings of kibana, but in this way the time of the application is also changed (in this case of 2 hours). How can I solve it?

I tried to use this into the jdbc_input_plugin:

jdbc_default_timezone => "UTC"

but nothing changes.

If you are getting data with different timezones depending on the source, then you could mutate+convert them back to strings, then run them through a date filter selected conditionally based on the source.