You need both. We've used Boomerang for parental controls. On a device with Samsung Knox, you can prevent the kid from working around and/or removing Boomerang. I think there's an article on the Boomerang web site on how to set them up together. Source: almost 2 years ago

I also personally don't use the built in parental controls but a 3rd party software on both daughter's amazon tablets and xioami phones. https://useboomerang.com/. Source: almost 3 years ago

Https://visualping.io does a nice similar job and is free for moderate personal use. - Source: Hacker News / 9 months ago

Could try visualping.io but it's not gonna be as convenient as coursicle. Source: 12 months ago

You can also monitor up to five webpages for free with VisualPing. Source: about 1 year ago

As a belt and braces approach you could try using something like visualping.io (others are available) to monitor the URL https://recruitment.raf.mod.uk/apply/applying-for?c=15&r=293&type=regular and check when the wording "THIS ROLE IS CURRENTLY CLOSED FOR NEW APPLICATIONS. PLEASE REGISTER YOUR INTEREST AND WE WILL BE IN TOUCH WHEN IT REOPENS." disappears, and it will send you an email when it detects a change. Source: about 1 year ago

Also I was using https://visualping.io/ to track the change. Like you can track the change on the button change for that particular page ( like the button being now back in stock instead of grayed out). Source: about 1 year ago