If you need to raise your price again, I would just say "as of Jan 1st, the price goes up". Period. If you wanted to be "fair" you could offer current users to prepay prior to Jan 1st the the current price giving them a few months break. The thoughtful consideration on your part was appreciated. I was one of those whose credit card expired right after the price increase so my benefit from the policy was minimal. I figured, oh well, I didn't win the lottery this week either. Maybe next week.
