By David Milliken LONDON (Reuters) – Longer-duration British gilt yields fell on Thursday, easing back from 20-year highs struck on Wednesday before the Bank of England bought 4.4 billion pounds ($4.88 billion) of debt at its daily reverse auctions – which are due to end on Friday. Thirty-year gilt yields dropped 13 basis points on the day to 4.76% at 0807 GMT, after hitting a high of 5.1% on Wednesday, according to Refinitiv data. Twenty-year gilt yields were 5 basis points down from Wednesday’s close at 4.85%, after a peak of 5.195% earlier that day. However real yields for index-linked bond…