Unless this just changed with the newest price increase, you've always been allowed to renew at the old price and get the old renewal discount if you were already in your renewal period when the price increase occurred. And if you think about it, if you already have the renewal letter in hand that says $699.99 - $60, how can they not honor that if you send in a check with that form? The one year they went from a $20 discount across the board to a tiered renewal discount the same thing applied. If you renewed at the old price you got $20, then you got the increased (or decreased for So Cal Select) the next year. I was in my renewal period for my premium that year and I got $20 off the then "old" price and was able to use the payment plan without a new 1 day deposit.
However, the OP's AP has already expired, so they may allow a retroactive renewal with the same expiration date, but they might not allow a discount. If the OP buys a new AP with a new expiration date, that's not a renewal.