Question about Huge Jump in Escrow Payment- Pending Foreclosure

[Austin Snyder]

Hello I'm newer to working on pre-foreclosure properties and I'm working with a seller to try to take over their mortgage "subject to." Their payment used to be about $400 but it's jumped up to $1,400 with about $1,000 of it going to escrow. They have several thousand dollars in arrears. I'm hoping I can get some ideas as to why that would jump so drastically so I can try to get it back down to the previous $400 so it will cash flow. Does anybody have any idea what could be happening here? It's just a home in a small town in Texas. 
Many thanks in advance for any help on this one!