Index template overwritten with default setup.template.overwrite false

in escloud

I've got some index templates with optimized configuration, yet everytime they are being overwritten, logs confirms it:
[instance-0000000011] adding template [winlogbeat-7.5.2-blabla] for index patterns [winlogbeat-7.5.2-blabla-*]

This log occurs every 10-15 minutes, existing index template name and pattern are the same.

I'm sending data directly from Beats with mostly default configuration, including this:

setup.template.name: "filebeat"  
setup.template.pattern: "filebeat-*"  
setup.ilm.rollover_alias: "filebeat-%{[agent.version]}-blabla"

documentation says:

setup.template.overwrite
A boolean that specifies whether to overwrite the existing template. The default is false.