@Borris If you have a special event coming up I would still go for it and join bootcamp anyway. Firstly you will learn what and how to eat with this approach; secondly you will get lots of ideas about how to reduce carbs and lots of support; thirdly you will be going into that weekend / event from a better base, and you will be able to get straight back on bootcamp when it is over.
However, what you should know and expect is that when you return to eating lots of carbs the excess glucose will be stored as glycogen. Each gram of glycogen is bound to 3 or 4 g of water. So you will most likely see a weight increase and may well feel bloated. If you have a couple of days of excess carbs it will probably take another 4 or 5 days (on strict bootcamp) to return to fat-burning, so you are effectively losing a week out of the 8 week programme. You might also find that eating lots of carbs re-ignites your desire for them, so you will need to be ready to be strict and determined once it is over, and in particular make sure you don;t have access to left-over cake / crisps / wine etc.
My advice for the actual weekend / carby period is to enjoy it. No point in feeling guilty. But maybe question why it has to be so carby, and find out what you can influence. e.g. a night away in a hotel with a big breakfast: avoid the fruit juice / prunes / cereals go for the full cooked breakfast - eggs, bacon, sausage, mushrooms, tomato. Ditch the hash browns / toast / potato scone.
If it's a pizza night, can you change that to a curry night (or similar)? Eat something like scrambled eggs about 2 hours before you go so you are not ravenous and more likely to eat mindfully. Drink lots of water, especially before you have any alcohol so you are drinking alcohol for the enjoyment, not to quench your thirst.
Avoid snacks. You don't need them.
If you're served a plateful of food eat more of the protein and helthy veg, leave as much of the carbier items as you can - e.g. eat the fish and leave the batter; eat the chicken, broccoli and carrot but leave the bread stuffing, the yorkshire pudding, the sweetcorn. Eat small amounts of what you really want (roast potato is my downfall) but notice whether you're really enjoying it, and stop after a small amount. You might find that eating a third of the chips is actually enough.
Avoid as much pudding as you can.