>>> The fact no one from AB has got in touch is,frankly both pathetic and worrying
AB isn't a massive organisation like Google. It doesn't have staff on duty 24 hours per day to monitor the site. It's run from a fairly small office building in Kettering by the staff of a digital marketing agency called SilverDisc Ltd. (Crunchbase estimates the total number of staff at SilverDisc as around 20). As such, AB's editors almost certainly have keeping an eye on this site as a very small part of a much wider role within SilverDisc, which they perform in office hours from Monday to Friday. Expecting anyone from AB HQ to see, and to respond to, posts on AB at weekends is simply ridiculous.
If Apple is sending out warnings about security data possibly being hacked into, it's extremely likely that they're getting their information from this site:
https://haveibeenpwned.com/
Even if your email address does show up there as having been 'pwned', it's not necessarily anything to worry about. If someone with nefarious intent has managed to hack into AB's server and steal your info, it's NOT really of concern UNLESS you're silly enough to use the same email/password combination elsewhere (such as on Amazon or for internet banking).