OK, ordered all 5 issues so far on 22nd Feb.
1-4 arrived in one (slightly flimsy) envelope on Feb 27th but no5 was missing, with no clue where it was.
Emailed them today (having given it a couple of days to catch up), and within 20mins I received a reply stating that no5 had got delayed by up to 10 working days, and I should have mine by 8th March.
Hope this helps some of you.