Roger,
CHC shall notify u vide email in approx 7 days that 'your file has been updated with your new address'. And another 7-10 days it'll take to change the e-cas. However, once u have got their email, the e-cas change or not, gets immaterial.
That timeline I gave is what happenned with mine (CHC-London) during Dec 09. In any case, rest assured that CHC/CIC had already worked on your request. This is something they usually do not goof-up with.
Hope that helps.