It is unlikely to be officially bootloader-unlockable (being a T-Mobile exclusive). But I'm expecting it is a Mediatek SoC, which has known security flaws allo

It is unlikely to be officially bootloader-unlockable (being a T-Mobile exclusive). But I'm expecting it is a Mediatek SoC, which has known security flaws allowing for bootloader unlocks, so uh, /maybe/. If by chance it is bootloader-unlockable, GSI (Generic System Image, generic Android custom ROMs) should boot just fine on it. As a reference, GSI work on Coolpad C558 (not flip-phone, but uh bar-phone I guess? not sure if the term still makes sense in the age of smartphones) - it doesn't work great on Coolpad C558 because of the severe lack of RAM, but should be ok on Cat S22. Some specifics will just probably need a bit of work for PTT button, and mapping long press on "#" to vibrator. Unless you want T9 on it, or to fix random apps's broken DPAD UX, there shouldn't be more than a day of work to be fully usable. Edit: If someone wants to send me one (in EU), I'd be happy to take a look