Can anyone clarify what is the birthday age cutoff for age groups, if they say have 10-young 12 and then older 12 group?? I cannot find anything showing the information.
that's right- the meet director decides and i'm pretty sure it is decided upon after registration is essentially complete and they "line up" everyone by birthdate and then divide them into even groups. they would then name the groups accordingly...some do like you said- "10-young 12" or some may just call them "Jr., Sr." or even just "A,B,C,D etc."
(the number of groups they divide them into would be determined by how many gymnasts there are in all divided by how many awards groups they will offer.)
this means there is no universal age/birthdate. it is different at every meet.