How to squeeze a little more out of TiVo.
 

A third party has informed me as to how you can squeeze another day out of the TiVo EPG:

By using the next item button, you can go forward in the Guide one day at a time, up to 14 days. If you have the Guide in Live Guide mode, you can see full listings on the right of the screen for the channels highlighted on the left. But by going over to the full listings and using the Page Down button, you can see another day of listings.

Do bear in mind that, due to some weird quirk, this last day's data isn't included in any searches. But you CAN set up recordings, Series Links, etc, from the last day's info, which may be handy if you're going away for more than 14 days for example.