It has gone a bit quiet, I agree.
The MX record for Critical Path is still there:
btinternet.com MX preference = 10, mail exchanger = mx-bt.mail.am0.yahoodns.net
btinternet.com MX preference = 1, mail exchanger = mx.bt.lon5.cpcloud.co.uk
Interesting that the CP A record for mail.btinternet.com has vanished though:
I wonder if it had anything to do with this: