I wonder whether the PRS is acting in breach of its own rules here. Rule 2(a) says

"By virtue of the rights vested or required to be vested in the Society pursuant to its Articles of Association, the Society shall exercise and enforce, in accordance with these Rules, and for the benefit of its Members and the members of Affiliated societies, all the rights and remedies conferred and provided by the Copyright Act..." (my emphasis)

Charging members to use their own works, and to take an administration fee for giving them back their own money several months later, doesn't seem to me to be acting for the benefit of its members.