I'm not actually living in Uk but am Brit

What you are doing is similar to a CKD form of low-carb diet, which is the way I live. It mostly used by people doing alot of gym work/weight lifting. And its very effective for fat loss.

Basically one eats low-carb during the week with a calories deficit, then at the weekend for between 12 and 48hrs one eats low-fat high carb foods at maintenance level calories or 10-20% above. The aim is twofold, 1. to replenish muscle glycogen for your coming workouts, and 2. to reset leptin levels and maintain your metabilic rate.

After the carb-up fat minimal if any fat has been added (studies showed about 0.3kg) and the fat loss is quickly resumed the following day or so.

Its not for everyone, but it sounds like you may be getting some of the benefits of it.

One other thing to bear in mind. Your body has converted to using fat for fuel, in the early stages, two weeks or so, this meant muscles etc were using ketones. But after this period most actual convert to using FFA's directly, which is thought of as a way the body reserves ketones for the brain. This conversion takes time, so does converting back. So even if you have a day off and are not technically in ketosis, you will still be a fat burner (in my experience the carb-up can be not so nice as its low-fat and my body wants fat!).

Planned refeeds IMO help fat loss (don't like the term cheat), but require some discipline.

Hope this helps understand what may be happening.

Now if I could only get you guys/gals to pop round and see my family in UK and convince them I'm not nuts