This is expected functionality, out-of-the-box.
Quick Connect will update a User's SIP Address if their edsvaLync-SipAddress attribute changes. There is a default Policy in place which builds this attribute out upon User creation, but there is nothing which will dynamically update this attribute if the sAMAccountName or any other attribute is changed.
It is possible to customize ActiveRoles Server and create a Change Workflow which updates the edsvaLync-SipAddress attribute dynamically when the sAMAccountName is updated.
For more information on creating Workflows, please review page 301 of the ActiveRoles Server 6.9 Administrator Guide