Neil Fairbairn, in his 1983 ‘Travellers guide to the kingdoms of Arthur’, mentions a Christianised version of the story. He says that at the end of the world the golden round table will rise to the earth’s surface and be carried up to heaven. The saints will sit round it to eat, and Christ will be the waiter and serve them.
He also mentions that at its yearly midsummer appearance, a flash of light from it briefly illuminates the sky, and then it sinks again. Nah that’ll just be the earthlights I reckon.