Adopted Core Strategy and Site Allocations NPPF Compliance - Public forum - Planning Advisory Service (PAS)

Hi I am dealing with a Council that is currently Reviewing its Adopted Core Strategy for NPPF Compliance, and, as a seperate process, has published an Issues and Options on a Revised Site Allocations DPD as this is not in conformity (in terms of housing numbers) with the Framework. Is it normal to have these two processes running concurrantly? Other authorities I have seen in the similar boat appear to be using one DPD to bring the whole thing (Core Strategy DPD and Site Allocations DPD) up to speed. Thoughts please... Thanks Rich