Travel and Subsistence over long periods

I seek advice on claiming travel and subsistence when commuting to the same city but for different clients. I understand that the Inland Revenue are now beginning to challenge the two year rule

I am doing some job costing and seek general guidance on travel and subsistence allowances. The business model is that I live in the sticks so successive clients may be in the same city and 98% of my work will be done on client sites. I expect to be caught by IR35. There are two centres of work Edinburgh and Glasgow; Edinburgh is the easier commute. Setting travel, etc against tax will reduce my deemed income by some £5000 or more so the Tax and NI saving is material.

Can I assume that I can claim the full cost of reasonable travel and subsistence for two years - I understand that the Inland Revenue are now beginning to challenge the two year rule

I recognise that if I work for the same client for more than two years then as soon as I know I will exceed two years I cannot continue to claim travel and subsistence

If I change client but remain in the same city for more than two years and my travel remains basically the same (i.e. only the trip from the station will vary) will I be able to claim beyond two years

If I change location how soon can I return back to original city - e.g. could I work for 18 months in Edinburgh, take a short contract elsewhere and then return to Edinburgh and claim for another 23.5 months

-- alandjones