User blog comment:B214/Volume 22 spoilers/@comment-27083298-20160831001909/@comment-10330822-20160910113934

Yeah, it happens before the tournament if I remember correctly. In fact, I'm pretty sure it happens even before the fight with Trihexa. Zekram was supporting Issei to become a Satan because he wants Sairaorg to try and become one out of competition with Issei. If Sairaorg is a Satan then he can't be the heir of Bael. I'm also pretty sure that all happened before Sairaorg got Regulus Rey Leather Rex Imperial Purpure.