For the purposes of an equal pay claim, can a woman compare their pay and conditions with those of any man?

No. Under the Equality Act 2010, a woman's comparator must be a man employed on "like work", "work rated as equivalent" or "work of equal value". In addition the man must be employed by the woman's employer or an associated employer, and work at the same establishment as them or at a different one where common terms and conditions apply. The comparator may be the woman's predecessor in the post, but cannot be their successor. A woman cannot rely on a hypothetical comparator unless they are claiming direct sex discrimination in pay and their case falls to be dealt with under s.71 of the Equality Act, in that a sex equality clause or rule has no effect because they do not have a male comparator. In this situation, they may be able to rely on their successor as a comparator.