Where I teach, it would be a case of the sets being adjusted at the end of the year ready for September, unless there was a pressing reason why a child was misplaced in a given group & needed to move immediately.
It would be very normal for the top quarter, say, of set 2 in year 7, to be out-performing the bottom quarter of set 1, & they'd be re-set for year 8 accordingly. Apart from anything else, year 7 setting is based on KS2 SATs, & they aren't a terribly useful measure.
To be blunt, neither parents nor students usually get asked their opinion! If you are working at a level that indicates you'd be best placed in a particular set, that's where you are timetabled.
For us at least, you'd have to be in the lower ability groups, rather than set 1 or 2, before it started impacting on options at GCSE - & being in the less able groups would indicate that triple Science (or in my subject double English) would probably not be the way forward in any case.
I'd advise emailing/ringing the subject teacher, but if your dd is keen to be in set 1 & is doing better than students who are in it this year, you do have a strong case for her moving up.