[Provided that, in relation to a building which becomes registered after the thirty-first day of December, nineteen hundred and fifty-eight, the power conferred by this subsection to authorise a person to be present as aforesaid shall not be exercisable before the expiration of one year from the date of registration of the building or, where the congregation on whose behalf the building is registered previously used for the purpose of public religious worship another building of which the registration has been cancelled not earlier than one month before the date of registration aforesaid, one year from the date of registration of that other building.]