Yesterday I contacted Amazon to find out why I have some "no-rush reward credits" expiring on March 1, 2020 and others that expire on March 15, 2020 when in the past it was always a group of them that expired about every 4 months, and then those that were expiring were all on the same day of that month each time.
Their response today was:
"I understand your concern regarding the expiry of the credits added to the account.
I'd like to inform you that expiry of the credits is no longer 3 or 4 times a year, or on yearly or monthly basis. The expiry of credits now depends on the date it has been added to the account and validity of credit changes from one to another.
We apologize if this has caused any confusion."
If this is an actual adjustment to the program, instead of the imaginings of only one customer service representative, it now will be much more difficult to save up credits for higher dollar purchases and you are more likely to lose saved credits as it will be difficult to track all of the multiple expiration dates that will be randomly applied to them.
Note: I think that changes were made when they added the additional uses for the credits as the verbiage has change on the explanation page as well -
"Prime Members Can Get a Little Extra Something With FREE No-Rush Shipping!
Get a promotional reward or instant discount on your order when you select FREE No-Rush Shipping at checkout. Don't need your order right away? With FREE No-Rush Shipping, you either earn rewards on future purchases or receive discounts immediately, simply for agreeing to receive your order in 6 business days .
You can use your No-Rush rewards towards purchasing a variety of things. Rewards can be used for buying eBooks for your Kindle, movies and TV shows on Prime Video, groceries and daily essentials on AmazonFresh, and for 2-hour deliveries with Prime Now. You'll see which No-Rush reward your order qualifies for in the offer at checkout. Rewards are automatically added to your account once your FREE No-Rush order ships, and are automatically redeemed on qualifying orders. This is just another perk of being a Prime member!"
It might be worth your time to check your accounts and see if you now have multiple redemption dates to keep track of & decide if it's worth it to you to use No-Rush during the holidays.