1. Dear Hannah, you should make your application for citizenship now, before you leave the UK for 1-3 years, as you have spent the necessary one year with ILR in the UK. Don't wait. Go ahead and make the application. Secondly, once you have ILR, you have it forever and you don't need to once again spend five years in the UK to qualify for citizenship again. You simply need to spend one additional year in the UK when you return and then you can apply for citizenship again. So, here once you have ILR, you have it forever and then you only need spend one year in the UK to qualify for citizenship, should you leave for a period of years.
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