No, you can have the season pass start recording earlier or on time, and end on time or later, but never to shorten the recording, ie: just record the first 10 minutes or the last 20 minutes. Unless you set a manual recording, but that only works for a specific time, ie: 11:25pm to 11:40pm every day/m-f/s-s and it will record whatever it is on at that time.
Series 2 (PLS, sold)
TiVo HD 1TB (157 HD Hrs, PLS, "652")
Juliet Basic (PLS)
OTA! OTA! OTA!
The TiVo Apocalypse begins on Sat 2013 Feb 16 00:00 GMT!