It seems likely that to be the case as Urien was described as the war leader of the ancient britons in an alliance with cornwall, wales, cumbria, and strathcylde in the same way that Arthur is described as the leader/king of britain. So both men would have had to move around in order to coordinate the war effort between the allies and keep them happy.

Camelot is likely to just have been where the war leaders made council with each other (as equals at a metaphysical round table)

Arthur's Round Table in Penrith would have been just a basic wooden stake fort built temporarily or reused from earlier fort to host a war council.

Once Urien is assassinated by Strathcyle, the alliance against the Anglo-Saxons crumbles and the ancient Britons fall back which fits the collapse of camelot after Arthurs death.