Versatility: alternate routing

[BestGear]

Guys

I am struggling to get my head around the alternate routing.

I have two PSTN lines and two IP trunks.

The PSTN have inclusive calls - the IP trunks cost for every call.

I need to route all calls by default to the pstn lines, and if busy, spill over and use the IP trunks.

I have setup the lines with for example 01 being the dialled digits, with the "converted" being 01 and the preferred box checked just for the pstn lines.

Likewise, there are entries for 01 again, this time the preferred box unchecked for the ip trunks.

I just cannot get any calls to go on the ip trunks when the pstn are in use.

What am I doing wrong!!?!?!??

David

[BestGear]

Ok..I am missing something (other than a reply with help!)

I have tried with no success to get this working!

When I busy the pstn lines it refuses to dial out using ip trunks.

I can delete the routing and use 760 or indeed the direct line buttons and they work, and likewise incoming calls on the ip trunks work.... so the trunks do work.

Can someone guide me through setting these up so that all calls go via pstn, unless pstn, then they go via ip trunks?

Thanks in advance.

David