Update brew-installed applications when migrating from Intel Macbook to Apple Silicon

Just yesterday, I've migrated from a Macbook Air from 2015 (with Intel-based processor) to a Macbook Air with M1. I've used the migration assistant for this and was pretty surprised that everything, including applications and settings, was properly migrated. Most of the applications were installed using brew, and running brew upgrade on the M1 Macbook caused an error first. After having installed Rosetta through softwareupdate --install-rosetta, brew was running perfectly. But I wonder how the best procedure for my applications might look like. Would later versions of them be upgraded from Intel-based applications to ARM-based when running brew upgrade, or do I need to change any configuration manually?