Expert legal advice clarifies the position about arrest other than under s24 of PACE
"s.26 of PACE abolishes all "independent" powers except those listed in Schedule 2 of the Act such as s.13 Visitors Forces Act 52 (arrest of deserters), s.49 Prison Act 1949 (prisoners unlawfully at large), s32 of the Children and Young Persons Act '69, s24 of the Immigration Act 71, s.7 Bail Act '76, plus powers under the Representation of the People Act, Mental Health Act and Repatriation of Prisoners Act"