will ISP peer with 2 local WAN routers?

Hi guys, I have a customer who peers via eBGP with Lightpath aka Cablevision (AS 6128) and Level3 (AS 3356) and wants to do some dual-WAN router redundancy. I have heard that carriers will sometimes agree to set up a /29 WAN subnet for a customer and peer with (2) customer routers. The customer is delaying on providing me with the proper circuit ID & contact information to be able to call Lightpath and Level3 directly and find out if they will do this, so I thought of asking this list. Is anyone aware if Lightpath and Level3 will agree to something like this? Thanks, Adam