Reboot your router and check. Not that it matters.
I read on the Sky forums that they're "sticky" but the IP at my flat changes on every reboot (and there's a lot) and each time this router here at my parents has rebooted it's changed.
I still have vnc settings in my phone that work fine, been there since I last changes the ROM about 10 months ago - had plenty router reboots since then.
Perhaps your bathroom light switch sends a DHCP renew request to Sky? (giggle)
I was about to ask if I could join in again, as I've not played this in years. I can't seem to join the server though, as it's out of date. I'm assuming my newer client won't connect to it.