What happens if client doesn't respond to SDS appeal in time?

[eek]

Correct. If the client was a bit smarter they just respond immediately with 'your appeal has failed, original determination stands' and they've met their obligation to accept appeals. Doesn't leave you in any better situation. I don't believe any appeal is ever going to work, particularly in larger organisations.

Contractors also shouldn't get themselves in to this at this point. Outside to inside then appeal still leaves you at risk.

It would be interesting to know if HMRC get site of a gig that starts inside and is appealed and moved outside. Definitely one for a sniff for them.

Appeals have to be documented but not reported - in reality the important bit is the SDS determinations that should be kept by everyone in the chain in case HMRC comes calling and asks for them.

And an outside SDS determination probably requires a lot more detail than any inside one were HMRC sniffing...