I was really good for the 1st 2 weeks of cruise, then I got a bit bored with being so bloody good! So had the odd treat, nothing really bad (couple of glasses of sherry!). I went on an all inclusive holiday 4 weeks into cruise, and thought sod it, EAT! Put on 5lbs, came home did 2 days PP, and lost the 5lbs. Normally if you a little slip up, any weight gain will just be water.
I can't actually remeber my 1st celebration meal, I remeber planning,, dreaming, drooling over thinking about what I might have though!!
I had a stone and a bit to lose, I lost 5lbs in attack, then 8 over the 1st 4 weeks of cruise, the remaining few pounds were stubborn, but they went eventually. Sometimes they like to come back!!
Like I said I had to tweek it to suit me, I don't know if all the dairy played havock with my hormones or what, but I was having periods all over the place and felt a bit emotionally unstable, so I changed to 2 days PP and 5 days eating whatever I wanted, including the odd cake, choc etc. and thats what I still do now, just not quite so rigidly.
Please make sure you drink loads of water, this diet can be a bit hard on the bowels and kidneys, so its really important.
You sound like you are really committed, good luck xxx