I'm not aware of any specific reference to this in the legislation, but GPoC is an opt-in for eligible councils, but of no relevance otherwise. Having said that, there is a vague item in the model standing orders list of agenda items for the annual meeting, numbered 5(j)(xii) "In an election year, to make arrangements with a view to the Council becoming eligible to exercise the general power of competence in the future;" but if you don't meet the eligibility criteria now it is not something that would normally be resolved within a short timescale and may have to wait four years until your next elections. If your only reason for non-qualification now is that the Clerk doesn't hold a relevant qualification, the Council could resolve to pay for this, but it wouldn't be in this year's budget if you're only considering it now.