I'm trying to remotely connect to home machine through Windows Remote Desktop (amongst other things, but this is currently my primary focus). I can do this fine using my home WAN's static IP (thank god for cable!) with port-forwarding, but I would like to access it from a subdomain of my web-site (e.g. home.mydomain.co.uk).

In the cPanel for my hosting account, I've gone into DNS zones and altered the A-record to point to my WAN's IP, which I thought should do the job, but I still cannot connect. When I ping the subdomain, I get my web-host's IP, which I guess is to be expected as I believe the DNS of the host domain is used first, then my server handles the redirection of traffic to the IP in the A-record. Is this the correct idea? Do A-record changes suffer from the same propagation delays as DNS record changes, as I suppose that could explain it?

(by the way, this thread confirms my thoughts that setting the A-record should be enough: Hostmonster Subdomain redirected to home server IP: How to ssh into home server using subdomain)