The residual value is now only good through the original expiration date.

Formerly, when you purchased a ticket and did not use the full value of the VDB, they (NW or DL - I don't remember who it was last time I used one) would issue a new cert for the residual. This new cert would start the clock over, with another year to use the balance. Now it is considered the same VDB #, with a singular expiration date.