Sch 5A para 24
(1) Where a period is described in this schedule (in whatever terms) as ending after a specified number of months or years— (a) if the final month has a day corresponding to the day of the month on which the period began, the period ends at the end of that day of the final month, (b) if the final month is shorter than the month in which the period began and so does not have a corresponding day, the period ends on the last day of the final month. (2) In sub-paragraph (1), “ the final month ” means the month arrived at by counting forwards the specified number of calendar months or years from the month in which the period began. (3) For example, if a period described as ending after 6 months begins on 31 August it ends on 28 February (or 29 February in a leap year).