Period of Grace election
If you have failed to let your property for 105 days, you can make a Period of Grace election to treat your property as though it was let for the 105 days. To do so, your property must have qualified as an FHL in the previous year, and you must have a genuine intention to meet the 105 days in the current year. This election can be renewed for a second year, but the initial election must be made in the first year of failing to meet the letting condition.
For example, if the property qualified as an FHL in 2019/20 but did not meet the letting condition for 2020/21, you must make a valid election for 2020/21 before making an election for 2021/22. The good news is that you have up to 31 January 2023 to amend your 2020/21 tax return to include the election if needed.