imho I would never plan a holiday during harvest time....
but If I did, Id probably water the shit out of it with a saucer filled with water under it and cut the lights off. I imagine you would have some really hay buds that would be wicked dry and never get the strain smell and flavor
Water the bajeezus out of them before you leave. Cut the lights off.
Hang some 1 gallon jugs with tiny pin holes in them over the plants. Or a 5-10 gallon pail with some tiny 1/16 hoses. Stick some tiny nails in the hose to slow the water to a trickle.
Just throwing out ideas. No idea really. Never tried to let a plant go over 2 weeks with no supervision, lol.
How much are you harvesting? If it's a real crop, screw the holiday. You'll be able to afford to visit for New Years.
My plants get about two feet tall and I grow in 3 gallon bags. I can over over a week without watering if I need to, and I live in the Mojave.
With the lights off, if you water them well and use a slow drip system, I bet you could make it two weeks if you *Really* need to. Just be prepared for hermies or dead plants. Hope for the best... plan for the worst.