That term lifetime award is not used by the DWP. There is an "ongoing" award. Some claimants with an ongoing award get a review date of 10 years and other claimants with an ongoing award aren't given a review date - but can still expect to be reviewed after ten years. Your last decision letter from the DWP will tell you the length of your award. If you can't find that, then you would need to ring the DWP and ask.
BIS
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