You should take last day of earning period claimed ... irrespective of paying date.
Its given in UKBA site see below :
http://www.ukba.homeoffice.gov.uk/worki ... /earnings/
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How we convert your earnings into pounds sterling (GBP)
Earnings made overseas must be converted into pounds sterling so that we can assess them. The exchange rate we use is the one produced by OANDA.
You should use the closing spot exchange rate on the OANDA website on the last day of the period for which you have claimed earnings in that currency. You can find a link to the website on the right side of this page. It is an independent website, for which we are not responsible.
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