The problem with keeping up with the show on dvr is that there are two different versions of the show...the main one on the Discovery channel that airs on Fridays, and the one that airs on the Science channel on Sundays.
The Sunday, Science channel version is a rehash show that is behind on the episodes from Discovery channel, but somehow way ahead on episode numbers...they must have started with last season as the first episodes of this season, even though they are totally different hunts. (It's even still called Treasure Quest: Snake Island on the dvr/search functions, even though it is just called "Treasure Quest" now.)
I watch an episode or two ahead of broadcast by searching for "on demand" episodes...they catch up on the broadcast, then list a couple more...but no commercials on those pre-broadcast episodes. Sometimes the next episode will be listed like: "Ep 9 Episode 13" like the name is "Episode 13", then it will correct and list it as "Ep 9 Payday", which is the actual name of the Discovery episode, and the "Episode 13" will end up being the Science channel rehash that will be listed as "new" and a rehash of like episode 6 or so....
Confusing...right?
I keep track of what I have watched by doing a search, and seeing what I have already watched, and what is next on demand or on the Friday broadcast, and ignore the Science channel ones, or ones with a much higher episode number than what is actually next.