Nothing in this Act shall entitle the proprietor or a registered user of registered trade mark to interfere with or restrain the use by any person of a trade mark identical with or nearly resembling it in relation to goods or services in relation to which that person or a predecessor in title of his has continuously used that trade mark from a date prior--

(a) to the use of the first-mentioned trade mark in relation to those goods or services by the proprietor or a predecessor in title of his; or

(b) to the date of registration of the first-mentioned trade mark in respect of those goods or services in the name of the proprietor of a predecessor in title of his;

whichever is the earlier, and the Registrar shall not refuse (on such use being proved) to register the second mentioned trade mark by reason only of the registration of the first-mentioned trade mark.