@Porcupine, I think you have the right advice from the AA site.
Its the warning lights you have to watch for, that should (get the dealer to confirm) indicate that the dpf has reached a certain level of soot and thats the time to initiate a regen. In other words, if the light comes on when your driving, try and find somewhere that you can get the heat up. I drove from Scotland to London (with overnight stop) in a dpf car a few years ago. Never had an issue with the dpf until then. Just as I drove into Canary Wharf the dpf light came on. I parked up, went about my work and when I left I just found a road where I could do 40/50mph. Within 3 minutes the light went off. Only ever came back on again when I took the car to london again, did a similar thing and light went off again after a few minutes.
Some cars (Citroen, Peugeot) use a fluid to help with the dpf regeneration. Every time you fill up, it injects FAP fluid into the system. This helps reduce the temperature needed for regeneration to 450 degrees, so is more likely to happen in town type driving. Yes, the fluid adds an extra cost (for mine £175 for 85,000miles worth) but there seems less likely that the dpf will mess up with town driving. Ive done 101,000 miles in my Citreon, had no issues with the dpf at all (except replacing the fluid).