3.4 to 3.6 : how to log deprecation warning in a particular log file?

Hello,

I am working on my migration from 3.4 to 3.6
As everything seems to be ok on my development platform , I want to set up a particular log file for the deprecation warnings.
Is that possible? For according to the cookbook, we can only use levels.
https://book.cakephp.org/3.0/en/core-libraries/logging.html#using-levels

That would be the migration process easier.
Does anyone have a clue?

Kitcat