In this work, new heuristic algorithms are implemented and analyzed for packet priority scheduling, in the downstream direction of WDM PON-based mobile backhaul networks. The main objective of the heuristic algorithms is to improve the time delay of the high priority packet delivery from the infrastructure to the end-users (mobile or fixed users). This is achieved through dynamic packet reordering and scheduling in different priority queues and wavelengths in a ring-based WDM-PON architecture that is utilized to backhaul mobile traffic. The heuristic algorithms implementing dynamic scheduling are compared in terms of the high priority packet delay for varying traffic loads.