They do seem to adjust properly for moving holidays (a similar issue to yours). I looked at one resort that got a great TP for weeks 51 and 52 for 2010. For 2011, week 51 is low because it doesn't include Christmas and weeks 52 and 53 get the high TP.
I have a floating Florida week with a Sunday checkin. RCI gives an extra 2 points of trading power (compared to other July weeks) to week 26 in 2011 and to week 27 in 2012.
The strange thing is week 26 in 2011 runs 6/26-7/3 and week 27 in 2012 runs 7/7-7/14. So neither premium week actually includes the 4th of July!
:hysterical: 