Here's the update, and I must say I am pleased!
TCIA, Brenda French of the membership services co-ordinator, emailed me back within two days to say they were going to work on the problem, yesterday they came back to say they were going to experiment by sending two magazines by different routes and for me to let them know which one gets here first. Really a personal touch I must say...
ISA , Danielle Deck, emailed yesterday to say they had sent out the missing magazines to me again yesterday and to let them know how long it takes to arrive...I did reply to tell them their address label was minuscule and very difficult to find against the background of the magazine.
Both TCIA and ISA April magazines arrived here on 6th May...
So, both organizations have stepped up to the plate. Follow up on your problems, allow them to help, don't just moan on a forum site!