The topic has been raised previously.  For some years,  the focus has been on consolidation withing the current coverage area,  rather than expansion.  For example,  Valerie Shawcross raised the subject at Mayors question time on 25 March 2015,  but received the reply: “As explained in MQ 2014 /3442, there are no plans to expand the scheme outside of the current footprint at this time.”  (see News for further info)