Just got off the phone to the relevant parties at Bristol Rovers and Rochdale.
Turns out that Bristol will not allow flags or drums into the ground. Drums because of local residents, and flags because of "health and safety".
Rochdale will allow flags in as long as they are under 1m poles, but will not allow drums once again due to residents. I've got the contact details for the guy there so if we have any problems with stewards then we can contact him. This means I'll be taking a few small hand flags to Rochdale for a bit of extra colour.
The ironic thing is, when Rochdale score, they blast music over the tannoys that would disturb the neighbours just as much (if not more) than a drum would anyway!