Yes Cottingham's the one near Hull (based at a former National Conference League club Cottingham Tigers, but this side fromerly played in the RLC as Hull Phoenix before relocating, and have now overtaken their host side, but I believe are the same club now) and East Lancashire are based in Darwen.
Bradford Dudley Hill have no intention of returning as they prefer the NCL (where they will have a higher standard once if as expected move up to Division 1 after this season) due to more guaranteed fixtures and pretty much no forfeits.
St Albans it depends on what happens as the league may become a northern region to the RLC Premier once Hemel (the only non-northern team) move up. The RLC Premier North having folded now 3 of the 4 surviving teams having moved up and the other having re-entered the Regional Divisions (Blackpool Sea Eagles, assuming Widnes Saints have dropped out as they scratched half their fixtures last year despite finishing the season). Either way I very much doubt they'd want 6 hour away trips every other week for a slightly higher standard compared to the RLC Premier South, South London having ruled out a move up for the same reasons.