I suspect she is just tired and exhausted - it's just that time of year. This is why there is a vacation time - it is necessary to recoup and recharge (even for six year olds). Our five year old granddaugher is also going through the same thing. I wish you the best ...
Set the clock earlier, so she has time to get up in her own time, with no hassling , let her get ready at a quieter pace , children do better in the mornings when not pressured so much . Make sure she is eating well , could be some low blood sugar going on and shes cranky before she eats , if you give her extra time in the Morns , she will have time to eat more breakfast and feel better in herself ....
I'd try to give her some special time, rewards for being a helper, and encouragement at home and use a positive approach to guide her through this. Bedtime should be early enough that she doesn't over tire as well. Good luck