@gpatel-fr So far it seems that reliably I will get a ring when calling somebody from the same network as me. From Lucky Mobile, in Canada, it rings when I call someone using Lucky Mobile or Virgin Mobile, both of which are MVNOs on the Bell Network.
I don't think I'm hearing any rings when not doing that. Calling 1-800 numbers yielded mixed results, but consistently it would ring or not ring for a given number.