Taken from the Benefits and Work Forum,
“I’m afraid I can’t offer you any sort of timescale because we just don’t know. Some people are hearing within 8 weeks, and some are taking up to 18 months. They are dealing with a backlog, and the majority of people are being given a video or a telephone assessment. Some people have been given a paper-based assessment, but I have noticed that many of the award lengths seem to be short.”
Please excuse spelling/typos. Apart from being a clot it turns out I had one on my cerebellum that's now causing various problems!