Retaking y12 with different a levels

My friend had this exact issue but the other way round, they hated a levels and wanted to do a btec at the start of yr 13 instead, unfortunately they found out just after late applications closed, what I'd suggest is doing it to the end of the year and going to do sixth form as well, probably dont put too much effort and just use that time to familiarise yourself with the a level content in case you want to start them at the start of year 13, unfortunately you are going to have to wait till the next application cycle if its at a different college. I picked up an extra a level like a week ago and its been fine lol.