Is there a reason why the game haven't been updated since April of last year? There's no onhold tag so I'm wondering
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... Because of Covid?
c3p0 put it nicely. Just to add a little bit to what he said. Despite what some people may mistakenly believe, the dev (HopesGaming) actually has a main job and what he gets from this game is not his main source of income. He's not a fulltime dev (like for e.g. PinkCake is for BaDik iirc) and does this as a hobby/passion project on the side (that's the situation with a lot of the devs on this site. There are some who are full time devs yes, but a lot more are part-timers).
Also, there were two things.
One, Hopes had a minor surgery which was around late October 2021, and he couldn't get back into work during early November due to the pain. Then as c3p0 said, he got Covid in early this month. He's mostly better now, but it impacted his work speed.
Two, the coming update is supposed to be "Season 1 finale", so there will be more content than usual.
I think during the update's development, Hopes put in an extra lewd event for Gracie if I'm not mistaken.
I'm no expert on term definition on this site, but if I'm not mistaken "Onhold" only applies when the dev him/herself announces their game will be put onhold officially either on their patreon/subscribestar etc.
It does not apply to games that are in active development (even though there may or may not be a long wait between releases).