http://www.legislation.gov.uk/ukpga/2016/25/section/32/enactedInvestigatory Powers Act 2016enKing's Printer of Acts of Parliament2019-08-16 Part 2CHAPTER 1 32 1 A warrant under this Chapter ceases to have effect at the end of the relevant period (see subsection (2)), unless— a it is renewed before the end of that period (see section 33), or b it is cancelled or otherwise ceases to have effect before the end of that period (see sections 24 and 39). 2 In this section “the relevant period”— a in the case of an urgent warrant which has not been renewed, means the period ending with the fifth working day after the day on which the warrant was issued; b in any other case, means the period of 6 months beginning with— i the day on which the warrant was issued, or ii in the case of a warrant that has been renewed, the day after the day at the end of which the warrant would have ceased to have effect if it had not been renewed. 3 For the purposes of subsection (2)(a) a warrant is an “urgent warrant” if— a the warrant was issued without the approval of a Judicial Commissioner, and b the person who decided to issue the warrant considered that there was an urgent need to issue it.