The mortgage terms will remain the same regardless of who your mortgage's servicing rights are sold to, however the terms on the servicing side of things can change from servicer to servicer. With all of the changes congress is proposing and passing, I would've hoped that mortgage servicing would've had a major overhaul... but no such bill that effects mortgage servicing has been proposed yet. So I'd ask Chase for a copy of their servicing agreement, it should outline the dates you need to pay by before a late fee is incurred. Chase has several different loan departments, some of their loans can be paid online and some a mortgage payment has to be mailed in.
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