I don't think so. When he crowned MC as the young leader, his speech mentioned he wanted to be the cult leader til he can't anymore, but he's now willing to let go and give it to their new 'god'. I think he's just waiting for MC right now to fully ripe and he will most likely retire and live quietly.
Please let it be so
It's almost impossible for the current cult leader to die now anyway. It's certain MC will take on the Murim Alliance Leader himself, which looks like the final boss. And knowing the Demon Lord's personality, he'll prolly let MC do it cause he knew he hates him. Most likely, the cult leader will just act as MC's rock and biggest supporter to the upcoming war with the murim alliance leader. Right now, there's no character that can equal the cult leader.
I know the ml needs to be the Heavenly demon but that means our current leader needs to die right? If so let's just keep this pace. May he go on adventures with this subordinates forever and ever