You wouldn't have any problem getting the 50 versus 40 if it was within the 14 days. (I had done one for a price change that went from 30 to 40 a while back, and it was no issue). But I think if you got the 20 off, since the 20 off is not still active, I am not sure how that would work. I was thinking the 20 off was specific to certain days and not price adjustments, but I could be wrong.
This was my thinking also.