CMC
The manual says 2000 miles for greasing and I believe anually for brake adjustment and seal replacement. So if you grease before leaving, you should shoot in a bit more along the way somewhere.
If I may, a word to the wise from the school of hard knocks:
a) I found on my 3326K with Dexter bearings a bit tricky to get grease into. Seems the wheels can stop in a position to block the grease passages. If you get it wrong, you can squeeze the grease gun till the cows come home and no grease will go in. If you move the trailer a bit, the grease goes into that zerk easily. So go around and grease all that take grease, move the trailer and get the obstinate ones.
b) the rim around the zerk that holds the rubber grease cover in place is sharper than most kitchen knives. At least it seems that way if you stick your finger in there and try to wipe the excess grease out. Don't do that. Use a Q-Tip or something equivalent, but not the finger.
Several of us know about that and have commented in the forum.
Have a great trip!
Bob