I solved my double text/sms issue by disabling VoLTE. This prevented others from seeing my double texts but if someone has it enabled, you may see their double texts. Until Rogers solves the issue with VoLTE, you may get it from other users.
Even the Note 4 has WiFi calling feature on the phone along with most other flagship Android devices but what I'm saying is that Rogers chooses not to support Android WiFi calling dispite the customer demand.
Doesn't look like Rogers in any rush to support Android users on this one. Apple paid up lots of $ for the exclusivity. Real shame though as many of us could use this feature for improved service.