The phones do have the ability to apply multiple numbers to one device. I don't see why this wouldn't work with overlapping numbers. Ideally for Customer Access Rep stations you would want calls to ring on all lines so I believe this is an available feature.
To assign multiple phone numbers to a phone, perform the following steps:
1.Log in to dashboard and browse to Phones > Monitor > Phones.
2.Click on the phone you want to assign a number to.
3.Click the pencil icon next to Public Number.
4.Click the down arrow next to Public Number.
5.Select a phone number from the numbers you have previously purchased from your provider. For more information on how to purchase more numbers, click here.
6.To add another number to the phone, click the down arrow next to Public Number again.
7.Select another phone number from the list.