In case of multi-stage type-approval of the special purpose vehicles defined in points 5.1 and 5.5 of part A of F1Annex I to Regulation (EU) 2018/858 granted at a previous stage in respect of the installation of a 112-based eCall in-vehicle system in the (base) vehicle shall remain valid, provided that the 112-based eCall in-vehicle system and the relevant sensors are not modified.