I've spoken to @Mick Bratley and Michael Tomalin regarding this and the consensus is as below
The time to start one is when we actually get to look at AEPGs plans and see, I suspect, that there is no provision for a new venue which is against the LP30 policy that is committed to in the Peterborough Local Plan. That is, I believe, the best angle of attack. Also we need to get as many people to make objections to the plan as possible, if we can get the objections in the thousands, somebody somewhere might notice and say, hang on a minute.