Hope joining the QC does not mean Selene doesn’t join. Remember they made it so characters can rotate in and out of the QC.
I think Selene will replace Magneto. Maybe Hope replaces someone like Kate, who is really busy with the Marauders. Or I could see Storm leaving the QC as it takes away from her duties on Arrako. Emma Frost gave up being White Queen to focus on the council while Jean Grey walked away from the council to lead a new team of XMen.
I think Hope being on the cover is so we don’t directly know the results of Selene’s bid. But the XMen are moving into a new direction. Magik is overextended bring a war captain, teaching Strange’s students and now teaching Krakoans, so she is giving up sorceress supreme of Limbo to the Goblin Queen.