I agree it would be great to be able to subscribe to notifications of new posts to different forum topic areas. This isn’t possible at present but I have added it to a list of requests maintained by the BAA Website Operations Team. Just to set expectations this may not be possible and if it is then it may be a while before it is implemented.
There is a page that shows the forum posts in order of last comment date, the most recent ones at the top.
So if you’ve not visited the website for a while you can look here to see all the posts since your last visit. You can get to this page by clicking the ‘See more’ link at the bottom of the 4 most recent topics.