I personally wouldn't think it mattered, there will obviously be inconsistency as you're changing days. I wouldn't worry about it too much...I'd just change and then start afresh. That's just me though Hope you get sorted, I'm sure someone will have more useful advice than me haha!
What if, you can't make class do you wanna go to another then return to your original class? Then how many days either side do you have before you've missed a week?