To receive automated outage notices via SMS is easy.  All you have to do is register for One-Time PIN services 

Whenever we identify a problem with ADSL services in your area we'll automatically send an sms - and a follow up when the problem is resolved.

For other services when you call in if our agent tells you it's related to an outage you can ask them to add you to the list for sms notification when the problem is resolved.