Foreign Tax Credit redetermination or?

I am US citizen who moved to UK in July 2013 to take a job. I paid UK tax in 2013 through PAYE system. I filed US tax return for 2013 and claimed Foreign Tax Credit for taxes I actually paid in 2013 (cash method - simply added all UK tax withdrawals which were shown on my 2013 UK payslips)
I was now told that I need to do "self assessment" - file UK tax return for year 13-14 (I got an extension and can do it without penalty till early May).
Apparently, I can claim 2013-14 as "split year", when I am partly non-resident, and get back some UK taxes (my employer paid me in May-June 13, before I physically arrived to UK - it looks like those payments are not liable for UK tax).
But if I do it and get some UK tax back, what should I do about my US tax returns?
It probably qualifies as a "tax refund" (PAYE is an approximation, and if I file this will be for the first compete determination of my 13-14 UK taxes). But is it a refund of taxes for year 2013 or 2014? UK tax year ends in april 2014..
US tax regulations say that if you get a foreign tax refund in a later year, it still should affect your US tax return in the year taxes were accrued. (Or accrued or paid?) But is not it for those who use accrual method? Taxes I am talking about clearly were accrued in 2014 (when UK tax year ended); it is not clear when they were paid (though refund would be because of the exempt income in 2013, it will be a result of a complete recalculation of all 13-14 taxes).
I would much prefer not to do a redetermination of my FTC in 2013 (which would result in me paying to US all UK taxes I could get back), but rather treat it as a decrease in my foreign tax in 2014 for 2014 US tax return. (If I get this money back, it will be in 2015, but I guess counting it for 2015 US tax return is completely incorrect)
Any advise very much appreciated

You are required to follow US tax code and regulations. The IRS explain foreign tax redetermination events and the process very clearly in the instructions for Form 1116.

Well, I do not think it is clear. It says I will have to file form 1116 for the year for which tax refund applies. But my problem is that tax year is not the same in US and UK!
Assume I will get tax refund from UK for UK tax year which runs from April 2013 to April 2014 (i.e. part of my taxes for UK tax year 04.13-04.14 is refunded) -  will this refund be applicable for 2013 or 2014 US tax?
If it would apply for US tax year 2013, I will have to file for tax redetermination for 2013 using 1116.
If it would apply for US tax year 2014, then, if I would not have filed 2014 tax return by the time I got the refund, I would simply state total amount of foreign tax equal to what I paid in 2014 minus this refund.
My question is - which case applies.
I would think that formally "by the letter of the law" it is applicable to 2014 (since UK takes into account all my income till april 6 2014 in order to figure out the refund, so those are not "2013 taxes"), and this is even though the main reason for refund is that some 2013 income is exempt.
But I  might be mistaken... I am very far from law/accountant professions, and just try to read regulations and apply common sense to interpret them.

You have to do the math. The phase difference between the US and UK tax years just means that you have to do some reallocation. It's annoying and means you have to be in your toes, but it sounds as if you are almost there, you just have to get comfortable taking part of each UK tax year to make up a US ax year. This is where US tax filing extensions become useful.


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I called IRS, and the guy there told me that I should take all UK refund for 04.13-04.14 UK tax year, and divide it in proportion of what number of days of UK tax year was in 2013 and what number was in 2014. I.e., roughly speaking, 3/4 of my refund would apply to 2013 US tax year, and 1/4 to US 2014 tax year.
This sounds reasonable. However, there is no mentioning of what to do in my situation in any official IRS documents (and the guy I talked with confirmed that it is not spelled out there) - so it might be his interpretation, or some kind of practice, rather then a set in stone rule.

This is a good and up to date summary of the law: https://www.fenwick.com/FenwickDocuments/Foreign-Tax-Redeterminations-under-905(c).pdf

Thank you. I found this one before and it was indeed the most reasonable thing I found on the net.
They are "kind of" talking at the end of page 6 about situations when US and foreign tax year are not the same - I should look at the cases they cite, it is probably exactly about that split IRS guy suggested to me.
Too bad.. I hoped I could push all refund into US tax 2104 (and use against other foreign tax), but it seems I will have to assign 3/4 of it to 2013 and then pay it to US..  :-(