You can request access to the officer data package. The way to do that used to be to add a post to a specific thread but see here:
If you’re interested in monitoring then another way might be to use the Streaming API. You can listen on a connection which will broadcast every e.g. officer update as Companies House register it. Pro - you can filter anything you want and you get this as soon as it’s available. Con - it’s a bit more effort to set up and you have to manage a script which will be running all the time.