In a case where a person is arrested by a constable under a relevant warrant, this Part applies subject to the modifications set out in section 57C.

For the avoidance of doubt, subsection (1) does not cause section 21(2) to apply in the case of a person arrested under a relevant warrant.

In this section, “relevant warrant” means any warrant other than one granted for the purpose of having a person brought before a court in connection with an offence which the person is officially accused of committing.