You'll have to watch weaning yourself off it. Your body will put weight on with a sudden increase in calories. Same as any very low calorie diet. I personally don't think its worth it, unless you go the proper hog and do a VLCD longer term... (like exante, tony ferguson, lighterlife etc) There's every chance you will suffer cereal all week, lose 6lbs, then put it on again next week.
Have you tried the Wendi plan? Its basically an adaption to WW points and indeed propoints, where you vary every single day how many pp you take in...
I've converted the points plan into what I think would work for the new pp. The [7] is your weekly 49 divided out into each day.
Day 1 [points allowance] + [7] +1 point
Day 2 [points allowance] + [7] -2 point
Day 3 [points allowance] + [7] +10 point **** leave at least 48 hours between this day and WI (do not wi on day 3, 4, & 5)
Day 4 [points allowance] + [7] -4 point
Day 5 [points allowance] + [7] +1 point
Day 6 [points allowance] + [7] -2 point
Day 7 [points allowance] + [7] -4 point
Example: if you are on 29 pp per day. Day 1 would be 29 + 7 + 1 = 37pp
Basically spreads out your week and shocks your metabolism a little without having to resort to drastic "starvation" measures.