What to do when updating environment (themes,plugins,WP)?

What should I do after updating my environment?

Generally speaking, whenever you update any files on your instance, you shouldn't need to purge the whole cache unless the update is causing some CSS/JS updates that will take effect on the front end.

That being said, there would be two situations to take into consideration:

1) If you update a theme or plugin that will affect the Front End of your website (in general they change CSS/JS on the front end) then we recommend force purging the whole cache (including static files, not just HTML pages) 

2) If you update WP core files, then you don't need to purge the cache as those updates usually affect only backend processes.