Well update is that IR35 reviewer emailed me this morning to say that my contract review won't be completed until the end of today. I've contacted my agency contact to update them on the status advising that a start date of Wednesday and not tomorrow is more likely in case of any amendments. Strangely I've received an out of office reply - the guy won't be back until tomorrow anyway. Forwarded it on to one of his other colleagues. Not sure there's much more I can do at this stage as it seems the person who can amend the contract won't be in the office until tomorrow anyway! I think they are just expecting me to turn up, particularly as they have not even chased me over the last few days to get my contract signed. ..