We're currently having an issue where by the calls will initially route via the GSM gateway, but when the channels are full the call isn't failing over to the next gateway in the route list, but given a busy signal and a "not enough bandwidth" message on the ip phone.
The Quescom 300 GSM Gateway is configured as the primary route group in the route list, then it should failover to the normal e1 links.
The following service parameters are set to false ( but were initially true)
Stop Routing on Out of Bandwidth Flag
Stop Routing on Unallocated Number Flag
Stop Routing on User Busy Flag
I'm not sure what's stopping the calls re-routing to the next gateway in the route list.