The token format only affects wallet-to-wallet communication. Mints don't know or care about token serialization.
quoting🎉 Update NUT-00: Cashu now supports binary-encoded tokens that save around 40% on token size compared to the previous format.
note1wux…5stl
The new token format starts with "cashuB" 🫡
https://github.com/cashubtc/nuts/blob/main/00.md#v4-tokens