I think from previous years, the timetable is usually released about 2 weeks prior to the festival. Would very much expect them to complete the lineup very soon though!
From memory acts generally start at about 5pm, obviously the bigger names on later.
The final acts of the evening finish early in to the morning, so never actually needed to go into lisbon afterwards! There always seems to be something going on at the campsite afterwards, but by this time its usally like 4am.
(Someone feel free to correct me if any of this is wrong)