It probably will be longer than Ch3 took, since each map does take a bit longer to make now because I have to make the animations too. I'm also mid way through implementing 2 big features, so I need to finish them too.
BUT, it definitely won't be a long as Ch4 took. That update's other features were really tough to implement so they took quite a while, whereas this updates features aren't quite as difficult. There's also the factor that I did just take a pretty big break from working on the Ch4 update after the Undertale map pack since I was burned out. I hopefully shouldn't need a break this time though.