You're 100% correct, it is a twice yearly newsletter.
It contains articles on changes or forthcoming changes to electrical regulations & associated regs that affect the electrical industry, plus lots of advertising.
I get it sent free of charge twice a year.
I believe you can register for Wiring Matters on the IEE website www.iee.org.uk
,but if you have to pay for it I don't think that I would bother.