It depends on when you bought the renewal voucher. If it was before the change last August, then it has an expiration date for longer, but it won't act like a renewal if you don't activate during your renewal.
For example, we bought my DD a renewal voucher last summer before this...it is good for several years. But, her pass expired in October (she has not yet gotten back.). When she goes this summer, that pass will date back to October and expire October 2022.
If she doesn't get back like planned, and never activates the voucher, then it would only be good for a new AP...paying the difference of course...but since they are not selling, she could end up out of luck.
Renewals are cheaper because they simply keep your current AP going. Starting last August...before the November 2021 suspension...any and all vouchers were given a one year expiration so people could no longer buy and hold for years.
Not sure when you current pass expired, but if you do not get their within a year of the expired pass, you may have trouble using that voucher toward an AP until they are back on sale and it will require you to pay the differnce.