Ok, to take this one step further, should your dd move to L5 during the meet season and qualify for states at both L4 and L5, then she would go to the L5 state meet. My understanding is if a gymnast qualifies for 2 state meets, you compete the highest level.
me.
No, it doesn't work like that. It's declaration date like the other poster said. Every state has a declaration date and it's different state-by-state. In most states, it's 3-4 weeks prior to the state meet. On that date, you have to compete one level and one level only from then until the state meet or you cannot go to the state meet. Declaration date is different than a qualification date which is the date you must earn a score to qualify to the state meet.
An example:
Susie competes Level 5 on January 5, January 20 and January 30 and earns scores in excess of a 33.00 (state qualification in Susie's state is a 32.00). She's struggling with some skills, so her coach moves her back to Level 4 for a meet on February 4 in which she earns a 31.00 (state qualification is a 33.00). Susie's state declaration date is February 10. Between February 10 and the state meet, Susie cannot compete Level 5 or she will be disqualified from the state meet as a Level 4.
Continuing - n this same state - the deadline to earn your qualification score is February 28. Susie goes to another meet on February 22 and earns a 36.00. Susie can therefore enter the state meet as a Level 4.
In most states, the gym doesn't send in a formal declaration, but the point is that all levels are frozen from declaration date until the state meet, although you can do whatever you want prior to that date.
Optionals have some loose rules about not being able to compete too far back in levels if you have competed at a state/regionals at that level in the past. In particular situations, you have to petition to drop back a level. This generally comes up when a gymnast has taken significant time off or is coming back from a serious injury.
Elites also have unusual rules about dropping back to Level 10.