Kwd Tfyl Rsyfr Sbaydr T700 〈Tested & Working〉

But if I instead use on it, or shift backward by 1 (A→Z), it’s not immediately readable either.

I get:

Given the phrase ends with t700 , it looks like a model number (maybe T700 from Terminator? or a CPU/gadget). Could the letters be from a QWERTY keyboard shift? kwd tfyl rsyfr sbaydr t700

If I apply an (A↔Z, B↔Y, etc.) to:

kwd tfyl rsyfr sbaydr t700

pdw guob ihbui yzbiwi t700 — which doesn’t look like English yet. But if I instead use on it, or