In the beginning there was Battlestar Galactica, which had a 7-year-old Noah Hathaway as Boxey, Adama's adopted grandson. Then came Galactica 1980, which was supposed to star Starbuck and Apollo, *but* neither of those actors wanted anything to do with it, so it was set 30 years later, with a 38-year-old Kent McCord playing a grown-up Boxey. It was terrible.
"The Promised Land" is a fan film with an odd agenda. Someone cobbled together a semi-coherent story composed *mostly* of G-80 footage, plus a lot of stuff grabbed from a half-dozen different movies and TV shows. It's not very good, honestly, but playing 'spot the clip' is interesting.
The conceit is this: The Galactica found earth in 1980, but rather than hiding, they basically contacted us (Not entirely willingly) because of a Cylon attack, and that's basically that. Then we jump forward 30 years (To now-ish) when Earth has built some new Battlestars and Boxey's son (Ben Browder) is about to head off on the first deep space exploration mission humanity has been on since before the Cylon War started (So call it 1060 years, give or take)
In other words, the purpose of the fanfilm is a pilot for a *NEW* Galactica series with a different premise. A spinoff, if you will.