U18's/reserve team question, possible bug?

When I begin a new save the U18s tactics can’t be changed by me because there is an U18s manager, but as soon as I set up my first teams tactics or even click onto staff responsibilities without changing anything, all of a sudden when I click on the U18s tab the message is gone and I can edit alot of the tactics of the U18s team such as team instructions and the starting 11.I started a new save and uninstalled and reinstalled the game but this keeps happening. Is this supposed to happen or is it a glitch?