FLR = further leave to remain
which can be applied for through any leave to remain (LTR) application form, be it FLR(M) of PBS dependant leave or FLR(FP) or FLR(O) or ....
The OP wasn't able to confirm whether the wife applied for FLR using the PBS dependant leave to remain form or FLR(M), as he clearly stated that he didn't remember. I believe he meant wife became ILR dependant in literal sense rather than from an immigration (status) perspective.
She became ILR dependant, literally, but applied for FLR using PBS dependant form.
Anyways, it is all sorted I believe
