I'm very frustrated with BellMTS right now.
I just discovered this week that I can upgrade my phone (past contract) to a Samsung S6 Edge for zero cost.
That's the theory.
In practice, BellMTS stores are telling me they haven't had that model for months now. The web site still shows it.
Also, because BellMTS stores are owned by many different owners, there is no central database that can tell you where to find stock in a particular model.
For my low-data subscription (2.5 GB) Bell won't let me get the S7 or S8 at zero cost.