As noted at 3.3 above, a discovery assessment must follow within a reasonable period after the underlying discovery. Furthermore, as discussed in Chapter 7, there are time limits which prevent HMRC from making discovery assessments after particular dates.
However, what is not expressly covered by the legislation is whether there are restrictions on when the underlying discovery can take place.
Of course, the discovery must precede the assessment. But can a discovery ever be too early? The case law gives two conflicting views.