Hey Melissa
Things are looking good! Very neat and clean job too
And since you are so neat and clean, I’d say timing of removing the clips probably won’t matter. And I would recommend giving it at least 8 hours before walking on it. And same when to start grouting fresh tile
Only reason I recommend knocking out clips next morning is because the thinset isn’t super hard and is easier to clean the joints.
As far as the tight tile….With a smaller floor like that and being porcelain, I personally wouldn’t worry too much about it. Try to scrap out what ever thinset is beside it. Cutting the tile would be a pain and probably end up compromising your waterproofing
Marble and large floors are where that is a bigger concern