That’s interesting. I called my local store and they have multiple iPhones that are unlocked and all their refurbished iPhones are unlocked.
I chatted first before I called my local store and here’s the transcript.

After chatting I called the local store and they confirmed they are fully unlocked, not what are known as Flex Phones. The store confirmed I could finance an unlocked iPhone through Progressive Finance.
Flex Phones are unlocked, but lock to the first SIM card inserted for activation. Most carriers will unlock Flex Phones after 40 days.