If a player had the "Serious Dedication" advancement and upgraded their world to 20w20a+, the advancement would get revoked from them.

How to reproduce:

1. Open a world in anything before 20w20a.
2. Break a diamond hoe. (If you are bored just /advancement grant @s only minecraft:husbandry/break_diamond_hoe).
3. Upgrade to 20w20a (or newer).
4. Open the advancement menu and find out that you don't have the advancement anymore.

Cause: 

The criterion name has changed. To fix it, an upgrade path should be added that converts the old criterion name to the new one.