If you are going to be using the forwarding to an outside number frequently, I suggest looking into getting centrex services on your lines. It also allows you to transfer calls out to any outside phone number without tying up 2 or even one lines on your system. It will also allow conferencing in most situations as well. If you have other locations it may reduce your cost to call between them, if you can 4 digit dial them. Check out your local centrex features and costs, it may be worth your time. Remember, for the duration of the non-centrex transferred call on the ACS, you lose the ability to use two lines per transfer offsite, for the duration of the call.
For instance,
Calls in
L1-TRANSFER OFFSITE A INBOUND
L2-TRANSFER OFFSITE A OUTBOUND
L3-TRANSFER OFFSITE B INBOUND
L4-TRANSFER OFFSITE B OUTBOUND
L5-TRANSFER OFFSITE C INBOUND
L6-TRANSFER OFFSITE C OUTBOUND
L7- OUTBOUND CALL
L8- OUTBOUND CALL
THIS IS THREE CALLS BEING TRANSFERRED TO THE 800, AND TWO OUTBOUND CALLS, NOW ALL YOUR LINES ARE BUSY.
Also, since you will allow transfer, instead of hanging up and calling the 800 number instead. Over time your volume of transferred calls will increase. This will quicken the time when you need to add more lines to the system in order to get a free line.
Also, if you have 4 AA's, I assume you have different incoming hunt groups? The system will often grab a line and possibly busy out one of your hunt groups, so callers get a busy signal when calling in to your office.
Outside transfers are great, but not really designed for frequent use, more so for the occessional call, or it ties up your system lines too much. Heavy usage transfers outside, the best solution on the ACS is the centrex transfer.
You do not always get what you pay for, but you never get what you do not pay for.