[jabl]

Sustainable aviation fuel (SAF) is a type of fuel that is ostensibly sustainable (however you define it), but fulfills all the requirements in the Jet A-1 specification. The idea being that they are completely interchangeable.

So it's just a marketing trick. They could just as well market it as "runs on standard jet fuel available at any airport worldwide". Ultimately it's up to the customer to decide what fuel they use.

Perhaps they are trying to attract investment from people who put wishful thinking (sustainable AND supersonic) ahead of common engineering sense.