I realize this isn't what you were being asked about, but I still felt like pointing out the anime got to this and the chapters leading up to it already by the end of Episode 3- it didn't have to dip into Episode 4. Yes, 4's the episode titled about Christmas, but the latter half of 3 focuses on the conversations about the plans for Christmas with both Itsuki and Chitose and then Mahiru, and then moves right into the Itsuki and Chitose party (which we haven't even touched yet as of this partial chapter- it gets covered in the conclusion of Ch 10 with .4) as the episode wraps up, fully encompassing the end of chapter 10 by the end of Episode 3.
Curiously, so far the only conversation or scene that hasn't been adapted into the anime, far as I can tell, that's been adapted into the manga is the one where Itsuki talks about his father's issue with him dating Chitose from one of the earlier chapters, but I know for a fact it comes up eventually, anyway, in the anime. At worst, the anime just seems to pare down the conversations and brings Amane's internal monologues to a minimum, so a lot of the stuff that will get outright stated in the manga might get more allusions instead in the anime, but the bulk of the important parts of the conversations seem to still happen.
I do appreciate the extra dialog, though, and the more expressive characters in the manga, but I have yet to feel like I really missed out on anything particularly significant to the actual storytelling, so far. Just stuff that helps hammer home points, ultimately.