Flex Lease - Merger

I am a long time Sprint customer (24 years) who currently is on a Sprint Flex Lease that is entering month 18.  I am confused as to the status of my lease at this point.  In November I wanted to upgrade to the Samsung Fold 3 that Tmobile had on promotion.  Tried online and also went to the store.  I was eligible for a upgrade at that point but per the store I was not eligible for any promotions even though the promo stated it was for new and existing customers.  The advice from Tmobile at that time was to wait until I was migrated or call customer service.   Fast Forward to now I am wanting to get out of my lease and upgrade to the Samsung s22 that will be coming out next month.  I realize I will have to convert to a 24 month plan at that time.  Is this going to be possible or am I stuck until Tmobile migrates us.