I hope the next chapter have NSFW tag!
There isn't (?). Not quite sure. We do see them naked in bed but they're cover so. Actually it isn't a direct follow-up of the chapter but still they seem to have gone another base.
pretty sure it's been implied more than once before that they've already rounded all the bases, yeah?
I don't believe so. They were making out on the trip, but when they got walked in on Maekawa says they talked their way out of it, which suggests they didn't go any further there. After that it was shown that Maekawa slept over, but Shimizu feigned being asleep. And given the way Shimizu is acting in this latest chapter, it seems pretty heavily implied that this is the first time they've gone this far.