Aircraft engineers are like Greek politicians get three together and you get five different opinions. So attempting to organise industrial inaction is difficult.
Attempts to unionise over the years have failed by and large. The CAA are the only people holding all the details of licensed engineers. One attempt to contact this group failed because the CAA refused to mail on a circular letter with all costs met by the sender, this would have kept all addresses confidential. The reason given at the time was "confidentiality". The reallity was they didn't want to offend Big Airways.
With the merger of ALAE and PROSPECT there is another chance for an aircraft engineers union. If people wish to take it.
I believe this bigger union could bring political pressure on to the CAA for another attempt to contact all the L.A.E's. The mechanics and others would follow if they could see a body that actually had some teeth.