some teams, especially in fall, end their seasons, and hold tryouts, before others. as long as a player is meeting their team commitments (practices and games), they should not face repercussions for what they choose to do in their own time (now if they are recruiting for another team at your practices or games, badmouthing current team in the dugout, etc., that is another matter).
Last summer, which granted was extraordinary in running so late because of no spring, DD was moving up in fall, and most of current team was not. We made it quite clear she was leaving, even after the coach indicated it would be a 13u team (couple of other girls were aging out of 12u as well, and he wanted to try and keep team together), and we openly discussed (including with the coaches) what teams she had tryouts for, what offers she had, etc. not badmouthing current team, but just being realistic and honest with everybody.
Last summer, which granted was extraordinary in running so late because of no spring, DD was moving up in fall, and most of current team was not. We made it quite clear she was leaving, even after the coach indicated it would be a 13u team (couple of other girls were aging out of 12u as well, and he wanted to try and keep team together), and we openly discussed (including with the coaches) what teams she had tryouts for, what offers she had, etc. not badmouthing current team, but just being realistic and honest with everybody.