stevensfo wrote: I will simply assume that I'm still tax resident in the UK. For many reasons, it would the best choice.
That is the easy case since you would simply do nothing, say nothing, fill out your SA tax return each year and I can't see any problem with that. It would appear to the UK authorities that you are just an ordinary person continuing to reside in the UK. The fact that technically you don't meet the test for residency won't matter. They are designed for those seeking to escape UK taxation and not those volunteering to remain subject to it
I do wonder what if anything would happen in practice if you "pretended" in that way to be UK resident but in fact were not. The authorities presumably can build a profile of who you are, where you are and what you are doing based on the pattern of interactions you have with government. So if you never again used the NHS, paid council tax, renewed your driving license and so on, would anyone notice or care? Effectively you disappeared yourself, and yet there you are every year doing your tax return, presumably with a UK address that works.
Not sure but I think that the "clean hands" principle applies here. You are not profiting from this very mild level of deceit so why would anyone care?