5.—(1) This paragraph applies to a person (“A”) who has an existing licence to keep or use a sealed source which, as a result of the coming into force of these Regulations, is a high-activity sealed source (“an existing sealed source licence”).
(2) A must apply in accordance with regulation 25 for a variation of an existing sealed source licence before the 6 months date.
(3) Where A fails to apply for a variation in accordance with sub-paragraph (2) before the 6 months date, the existing sealed source licence ceases to be a deemed permit on the 6 months date to the extent it relates to a high-activity sealed source.