I believe most of the techs now always add oil to the 'book' amount for 2021 Turbos, given that it's such a well-known issue.
So going forward you'll want to check immediately after the oil change, in order to find the actual starting oil level, regardless if you change it or Mazda does.
Hopefully you already know this, but I'll mention it just in case you don't. Oil level is checked on all of these Skyactiv engines after waiting at least 5 minutes after shutting down the engine. I believe the consensus among DIYers here is that it doesn't matter if the oil is checked after 5 minutes, or cold the next day, because the level will be the same. Of course, if you're changing the oil yourself, you'll probably want to check it and add more (if necessary) at the same time the oil change is done, so that would be the 5+ minute wait after shutting down.