Hi, abstaining from food whilst doing this helps you to examine your relationship with it. If you can break those bad habits then re-introduce food sensibly you can maintain the loss. I did lighterlife 6 years ago and didn't do the maintenance program (useless counsellor who I resented paying!) and although it took 6 years and some life changing events it did all go back on.
Exante can be flexible and you can choose your own pace and decide when to refeed for yourself. There's always the option of doing another week of total if things aren't quite working.
Good luck if you decide to give it a go, but don't worry about what happens afterwards until you get there. There is no magical reason why people regain after a VLCD, simply a return to old habits.