A couple of weeks ago I booked flights for a family trip to use up the rest of my Early Returns points flying from SFO-MCO via DIA. I just received notice of a schedule change so that our flight that originally was scheduled to leave SFO at 9 am will now leave at 6 am, giving us a 4.5 hour layover at DIA and departing significantly earlier. Because we now live in Sacramento, obviously driving to SFO at 3am only to wait at DIA for 4.5 hours with 2 kiddos isn't ideal. I'm currently considering flying from SMF-LAX on WN either the night before or the morning of as F9 has a flight leaving LAX-DIA at 9am. However, this flight only has a 30 minute layover which concerns me since the next departing flight is a red-eye which we deliberately want to avoid. I haven't flown with F9 in ages so while I'm prepared for their ULCC model I'm not sure about how on time they are. Any recommendations based on this scenario?

I'm contemplating just switching to WN for the flight but I really want to get rid of these Early Returns points and this trip will give me a pretty good value for them, I just don't want a nightmare...