There are both elements of accuracy and contradiction in Dave’s response.
A Cllr cannot be appointed as an officer - whilst I’d agree, a Cllr cannot be a PAID officer of the council, there is extensive and widespread example of Cllr temporarily performing ‘officer’ role such as that of ‘proper officer’ during clerk absence or vacancy.
Custom and practice and, subject to checking, I suspect also no actual prohibition for a Cllr to be an ‘officer’ of the council - be that ‘proper’ or RFO (so long as they are not paid)
That is the straight forward part.
The slightly more contentious part would be the assumption that it ‘might’ be appropriate “for a suitably qualified Cllr” to undertake “some” parts of an RFO function whilst simultaneously suggesting that a “small council” (£12-15 p/h) clerk would somehow be organically qualified for the RFO function.
That, I’m afraid, is just not credible / real.
Chair of PC should perhaps not be a bank signatory anyway - in an ideal world.
To combine chair + bank signatory + RFO well, that’s just a bit silly