Some more food for thought on the subject:
I have seen MANY people "take a break" while on vacation and then struggle to get back on P1 (or completely disappear). There is surely something to having momentum on your side.
Another thought: What is "a break"?
A week or 10 days of eating/drinking whatever we want?
This is how we got overweight or obese in the first place.
If you read about the maintenance plan, it would only allow for straying from more regimented eating one day per week (some call it a "cheat day". I call it a "fun" day because on P4, indulging for one day is NOT cheating).
So, for a maintenance plan, even on vacation, one would choose the one day for an additional indulgence.
When we look at it like this, we realize that the plan is for life and if we don't learn a different relationship with food, we are destined to repeat history.
A vacation is a perfect opportunity to begin to learn to develop this new relationship.
My first vacation was 5 months into P1 when we went to Fort Lauderdale. The only exceptions I made were to have some P2 days, just because it worked better into my day than P1 (due to increased restaurant eating). I had no alcohol or other carby indulgences, only the additional meal (for example, a spinach salad with a chicken breast for lunch instead of a shake or bar w/veggies). My go-to drink was club soda with Mio (at home I use sparkling water from my Soda Stream so I guess the club soda was also an indulgence).
When I got home, I felt SO empowered. I really felt as if food didn't control me or my vacation. I proved that fun could be had without snacks and/or alcohol. I had begun to put food in it's proper place. Food is to nourish our bodies. I had to learn that food (and drinks) cannot be entertainment for me. AND it was the first vacation I could ever remember when I returned home without added weight to lose