moving schools in Year 6 - should I/shouldn't I

[geekgirl]

I am considering moving the children (10, 8, 5) to a different local primary school for a variety of reasons.
Originally I was thinking about moving the younger two next September, when dd1 goes off to high school. I am now wondering whether I shouldn't just move them all this term .
Dd1 isn't particularly happy at the current school, she doesn't really have any solid friendships (the school they're at at the moment is next to a US military base and has a constant turnover of children and a very high percentage of Americans, as a result is unpopular with locals so not many village children attend), and she does know a couple of children in year 6 at the other school. She's very academic and a bit of a 'nerd' so wouldn't have problems in that respect either. She has frequently expressed the desire to switch schools...
Should I leave her where she is for the time being? After all she only has to wait another 10 months until the she leaves. Or should I just move them all now???

[1dilemma]

If dd1 is the 10 year old and she isn't happy and wants to move could she go and look round the new one and then move if she likes it.

TBH'd probably move them but I didn't move schools a lot as a child IYSWIM