When setting a Ring Group with a Ringall strategy calling 2 Classic Extensions simultaneously, the calling party doesn't hear a ringtone indicating the call is in progress.
If the Ringall strategy has only 1 number, than the calling party hears the ringtone.
I have same problem:
Moving office for a few months so incoming calls need to be forwarded to several classical extensions at the same time (mostly mobile phones).
But the solution discussed does not work for me.
Only when I have one classical extension in a ring group, the calling party gets ringback tone.
I solved it before by setting a ring group with external numbers (followed by #) AND including in the ring group a dummy SIP extension " that really rings" ie that is registered in ATA hardware. But thats not easy and requires hardware.
If the moderator would have a better solution I would really appreciate to hear.