2 questions:

1) Do you have the 'Remember batch entry fields' options selected in the 'File Options' screen? If you don't see this setting, that means the Sept 2003 PTF has not yet been installed (and the Remember option will always be set).

2) Did you enter any credit or debit notes for this batch?

We are aware of one situation where entering a Credit/Debit note resets the Terms information to something likely not desireable. This has not yet been addressing in a current release.

If you have only been entering invoices and no credits/debits (or possible retainage) then this behaviour is unknown.