That's what I understand as well and regardless of 2020 or 2021, if you do this and are tuned, you will need to bench unlock so you can re-upload the tune.
Doing the update does not lock the ECU indefinitely. Someone please correct me if I'm wrong.
I’ll wait for Carbahn since their tunes automatically adjust to fuel type (versus flashing for octane) and offer a warranty. Not to mention the thousands of hours into R&D they put into their product.
Especially if this going to be a $1,500+ endeavor, have a warranty included, may as well...
Not sure if you all follow Matt Farah with Smoking Tire but he had Steve Dinan on his podcast to talk about his M8 with 900 HP and his tuning philosophy. Great listen if you have the 1.5 hours!
tldr: many canned tunes are unsafe and literally have the knock sensors deactivated.