I hate that the Byleth X Ferdinand B support is locked until post-time skip. I misssed out on recruiting him and Leonie because of the stupid locked supports. I wish there was an indication for a deadline until when you would need to get the locked supports like with the paralogues. I could have easily recruited all recruitable students on my first playthrough if it weren't for them but there was no way my armor rank would get high enough for Ferdinand in time.
Spoiler for post-timeskip Blue Lions plathrough:
