Your response got me interested whether it is true that Ancelotti is planning to leave the club or whether Perez decided to replace him with another coach. I don't know where you got your information from, but as far as I can tell,
this source seems to know and state the opposite. They say that there has already been a discussion between Perez and Ancelotti and both came to the agreement that Ancelotti will stay for another season despite the rather average season they played so far.
I think it is great that Ancelotti will be around for another year. If that is his last season ever, I wish him great success and an enjoyable end of his career. He will be missed.
With the transfer conditions not very good, I won't be angry with Anceloti if I become Perez. Two trophies shouldn't be too bad for Madrid this season. So giving the option of one year and freedom of shopping certainly provides another good opportunity for him. Maybe after that Perez has the right to decide Anceloti's career henceforth. Anceloti this season does not have ideal players. The hectic schedule of old players, that is their main factor at the moment.