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I hold a spousal visa. My first visa was valid from 2009-2011. I then renewed this visa, which was valid from 2011-April 26 2013. We traveled to America early in April to visit family, and my husband's grandmother died in the UK while we were away. It was a stressful time, and I honestly didn't even think about it. I only realised it had expired last night when I was going through my wallet.
Ah yes. My husband is British, I am American. We do both plan to remain in the UK working and living.