If Ame is 99% graduated, then Gura I feel is at almost the same boat at 90%. Gura has streamed much less than Ame over the past year (at just about half more streams - 36 to 56 streams), so I was actually expecting Gura to graduate before Ame. So what I'm thinking is that Gura is already more or less graduated already, but Gura as an IP and the status of most subscribed Vtuber of all of history, tells me that Cover is just BEGGING Gura to NOT officially graduate (or even 'retire' like in Ame's case). They'll do practically ANYTHING for Gura as long as she streams around 3 times a month to keep her internet visibility alive, and participate in various group projects and paid promotions so that sponsorship money can keep coming in.
Back to Ame, the 'sane' take is that probably Ame is at the point where she made enough money that she can officially retire IRL, especially with her still getting royalties from her character appearing in future streams and future merch runs.
But my own 'batshit insane conspiracy theory that has no basis on reality' speculation? Ame is getting married IRL, and wants to dedicate her near future to building a family. Perhaps after having a child or two, she will be back to streaming, but that's a longs way off and so this is the compromise Cover is willing to give her. Reasons why I think that are:
1) Despite what the fandom thinks, especially with the rampant AmeSame stuff since the beginning of Myth, Ame is the most "het" of EN, tied with Shiori and IRyS (the latter is heavily suspected to be married IRL). Their collective love of Otoge, BL, and bishis are big signs of your typical female het otaku, and since we know Sachiowo had a BF before Myth, she may be looking for a more serious relationship this time around
2) She pretty much already has the same contract Gura has in that she only really has to stream a few times per month (perhaps Ina has the same contract?), but if even she can't do that, then that means SOMETHING BIG happened to her personal life
3) Ame has stated before many times that she always been the one who prefers to work behind the scenes, and since she has explicitly stated she isn't even joining the staff side of HoloEN, then we can assume her future endeavors are COMPLETELY different from vtubing/streaming and what goes on behind it as a whole
Just my 2c on the matter.