Seems like they are changing bank partners and will use cards that code as "charge card" instead of "prepaid card" which is great (some places block "prepaid" cards) but they are forcing this change on everyone (as much as I could see) and doing it with only 30 days of notice, which is much less great.
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Sad they couldn't keep existing cards open till they expire, but just recently their card expiration dates jumped to lasting till 2027 so I see why.