Locked pots are something which has come up recently, maybe check out the threads below
One of the recurring things is the amount of friction there should be around unlocking a locked pot. Monzo got burned early on by having customer ops staff as the only route to unlock a locked pot early, unfortunately they were overwhelmed by requests to unlock early, so opted to let the user have control of the lock
I can see value in having the goal target as an option to unlock (and it would encourage saving quite well), I’ve not used goals so not sure how much fanfare there is about reaching a goal, maybe worth considering if a change there or to the lock is better