My daughter is 8 and I finally sat her down and had a talk with her. I think it was in her 2nd grade classroom when she didn't want to leave AGAIN one afternoon.
When Katie is in bed, she wants to stay in bed.
When Katie is at home, she wants to stay at home (and fights going to school)
Once at school, she doesn't want to leave school, and will come up with a list of reasons not to leave (like sharpening pencils for the teachers).
Once at home, she doesn't want to go to swim practice.
Once at swim practice, she finds every reason to linger, "help" her coach with the next group...
yes, her whole day is like this, from getting into the bath, to out of the bath, to resisting bedtime.....
(And yes, she is sensitive to feelings and irritations like seams on socks.)
Once I pointed out that she struggles with transitions, and it's how she has always been.... and whatever she is doing she wants to stay doing.... she got a laugh out of it. She agreed those are her big battles, and the feelings feel very real & important at the time, but once she transitions it is okay.
Did the talk solve everything? No. But it's gotten better and more often than not I can say "Are you having a transition problem? A Katie likes to stay doing what she is doing, but you know you will get stuck in the next thing, so lets just go to it."
(and yes, we have tried to make her life structured & highly routine so it's predictable, but it just made the battles predictable. Self awareness of her quirk seems to have helped more.)
Hope this helps!