That was on 23 June. I followed up by email last week and was fobbed off with "we have identified the problem and will be pushing out a solution early next week" (i.e. early this week). Nothing seems to have happened since, but I can't be sure as this screen is now repeatedly blocking my access:
I'm not using a VPN and am accessing the internet from home, i.e. not from a public network. Using Firefox 102.0.1.
First, the problem with the schedule alerts has been fixed.
Second, the captchas show up due to suspicious behavior or IP address. Either way if you solve the captcha you won't be blocked.