Dual DHCP WAN up addresses

I have 2 DHCP WAN addresses that I pay for. Only one WAN IP is able to work at a time. I was wondering if there was a way to get both to be provisioned and utilize the extra WAN IP that I pay for. I'm using an Arris S33 modem. Previously I had 4 WAN ips but was told there is no way they would allow me to continue that on my plan. I really need that second WAN address to be working for my situation. Any help would be appreciated.