Don't do it yet. We had an issue where the drush updb failed.
A fresh install then drush updb did work but simply updating drupal and civicrm with composer then running drush updb left database in a state where it could no longer be updated by drush.
I have no idea where the source of the issue is but the updb was complaining about null values in the database.
We ran the drupal8/civicrm install from scratch then updated the db and it worked fine.
Here's a link to the relevant drupal upgrade complaint thread: https://www.drupal.org/project/drupal/issues/3052464
Luckily we try all of these things out in a mint copy of production vm first, before we actually do upgrades. This issue may or may not occur for you. Be careful!!!
-Neil