If he ages them up I will go from Tier III to... Tier III to then. (They were going to be after a timeskip later on anyhow what are the lolicons malding about?

BaiBai will get my money no matter what on that end )
I'm kind of new to the timeskip discussion; apparently it was talked about before the censorship shit hit, so I went to Discord and searched for it, and what I found was Baibai saying that he would maybe do a timeskip on the summer break or on a couple of days at a time. I assume this was to skip dead days where MC didn't advance much with the girls. So no, unless we are talking about an ending-type time skip to see them all older after the game ended, I don't think he planned to actually continue the story after a time skip big enough to make the character look older.
And in my personal opinion, it just doesn't fit with how the story has been progressing. I mean, the MC has been back in the past for A WEEK, and he has already:
-Got his hands on his mother to the point of making her climax in a "massage."
-Got Alyvia to fall for him (in the love route) or having the mouse and cat game with her (in the corruption route).
-Made Emily become his second girlfriend willingly and almost had sex with her.
-Made Lola a third girlfriend and help him with the harem
-Got Stephanie as his girlfriend and made a lot of progress with her (willing to creampies in pure seduction or with choke play in corruption)
-Got his teacher to give him a blowjob and promised to go on a date with him.
-Made up with Victoria (in seduction) or started taming her already (in corruption).
-Got a sexual interaction with Viktoria's mother and even told her that he would take both of them.
-Made his crush start developing feelings for him (in seduction) or blackmailed her for sexual favors (in corruption).
-Got Mya to almost fall for him after eating her out.
-Convinced Gao about him being a time traveler and about working with him to be rich.
All of that in A WEEK.
If Baibai were to make a timeskip of a year or so, it would be very hard to make it believable that the MC suddenly slowed down and made 0 progress with the girls during that timeskip. And if he did made progress off-screen, the fans would be pissed because that content was skipped. With MC's days being so fucking packed, I can't see a timeskip longer than a few days unless it's an ending timeskip, so that thing about the timeskip is irrelevant if it was only intended for the ending or if it was never intended for making them older.
Now that I have written all of MC's accomplishments so far, I have to say, if I had read that summary without playing the game, I would have said that the game was being rushed, but since I played it, I actually have to compliment Baibai. I never felt like it was rushed or illogical while playing; all events seem well placed or developed believably enough in my opinion. I have seen other games go from 0 to 100 from one event to the next and break my immersion, but this one never did.