This was announced a month ago:
SLB Mobile Launch + Update - Critical News | WhatIfSports.com
"Separately, we want to give everyone a heads-up on an account policy update.
Beginning March 24 at 11:59 PM ET, purchases on WhatIfSports will be able to use credits for up to 50% of the purchase price, with the remaining amount paid using standard payment methods.
For most users this will not change anything - the vast majority of purchases already fall within that range. If you currently have a larger credit balance, you’ll have the next two weeks to use credits normally before the update takes effect.
Importantly, existing credits are not being removed and the credit earning structure will remain the same. This change simply updates how credits can be applied to purchases as we continue modernizing the platform and investing in new improvements like the SimLeague Baseball mobile app."