I just went away last week myself.
What I did was I worked two days ahead of schedule before I left, then came back 4 days later, and spent 2 days working with 3 other guys, (friends) to finish up and then went back to join the family camping.
Yes, sadly it took 4 of us to do 3 days work in 2 days
Yes it sucked to have to come back, but thankfully we were only camping 2 hours away.
I also am able to pull this stuff off because my customers are given a day to be mowed, however they all understand that sometimes I may be a day or two early or late due to weather, breakdowns or vacation, lol. I am sure if I abused this then many would have issues with it, however so far I have never had issues.
Hope this helps you brainstorm a solution for yourself.
BTW if i was your customer and you skipped me, or missed me one week for any reason and tried charging me more for a double cut I would find someone else. I think that double cut prices are a way of dealing with problem customers only. You know the ones who say don't come this week, or don't come till I call you, etc...