In the second episode, at about the minute 3 mark (October 1st), Airi Hasekura lends Yui Furukawa a spare uniform she had in school. Airi's bow-tie is orange, and I think the bow-ties' colours have something to do with either the students' year or their class. If that were so, it'd be reasonable to assume that the spare Airi had would have a orange bow-tie. However, the first image we see of Yui shows her with a green bow-tie:
That would have been fine, if for the next minute or so the bow-tie didn't change its colour from green to orange and back four times:
So the bow-tie is green when first seen at 3:07, orange at 3:16, green at 3:30, orange at 3:44 and green again at 3:53.
On the next day (October 2nd) Yui's bow-tie is consistently green. I'm assuming the bow-tie was supposed to be orange on the first day and green on the second, presumably because she would've gotten a green bow-tie meanwhile. This assumption also comes to the conclusion that this was an animation mistake.
However, since there was a "time-quake" at the end of the first episode, it came to my mind that this could have something to do with the plot. But since that minute was the only one where this change was seen, I was more inclined to believe this was a mistake.
So basically my question is: Were the switching colours of the bow-tie accidental or were they intentional (thus being plot related)?