Tier 3 support resolution timeframes

I have an issue where Xfinity application (website and instore tablets) will not allow me to upgrade my mobile device on my existing line because for some reason Xfinity system thinks I don't have an existing line even though I have been an Xfinity mobile customer for nearly 3 years and have a Xfinity mobile account number.  I went to the local Xfinity store where they called in the issue to Xfinity support on May 12 to correct the issue.  My understanding it went to Tier 3 support.  It is now a week later and the issue is still unresolved.  I called the Xfinity mobile support number and the only information I get is that the issue remains pending with Tier 3.  I get no information on when this issue will be addressed.  As a former IT guy I know tickets have priorities and also a timeframe for resolution yet I get no information at all on when this will be fixed.  I am guessing there is some field on my account record that is incorrectly checked or not checked.  I find this very frustrating as a customer not to be provided any information on estimated time to resolve.  I do want to take advantage of the current promotion I received to upgrade but that will expire in a few more weeks.  I had been happy with Xfinity mobile up until this point but this issue is starting to change my perspective.  If anyone from Xfinity monitors this board please provide any insight on how I can help move my issue along within Xfinity tech support.