Yeah 8 1/2 stone altogether so it's likely to be quicker, but when I did SS a few years ago I started at a similar weight and I'd say my losses have been just as good this time. So like for like I don't think there's much difference in the weight loss. Having done Cambridge before I would really advise moving up the plans instead of stopping. I lost 5 1/2 stone last time and wanted to lose another 1 1/2 stone so came off and planned to do my own healthy eating. Clearly that plan did not work as I wouldn't be back here now lol Stabilisation and maintenance are so so important, much more so than the weight loss in my mind.
You could have the yoghurt as breakfast if you wanted, maybe with a bar too? I add a pinch of the water flavouring to my yoghurt and it tastes lovely! Definitely don't use more than a pinch though, otherwise you'll feel as though you have a whole pack of refresher sweets tingling away in your mouth hehe
I really understand the feeling out of place thing. Weirdly, the only person who knows I'm doing Cambridge is my consultant! I live on my own which makes it easier and I'm a community midwife so I spend all day driving around visiting pregnant women and new mums which means I'm on my own at lunch time and can easily have a bar with no one knowing. My friends/family think I'm doing my own low cal/low fat/low carb/healthy eating diet so if I eat in front of them it's fairly easy to stick to 810. I have had quite a few dinners out (a wedding, a date, dinner with a friend, friends coming over for takeaway, etc) that haven't been 810 though, although I've tried to eat as healthy and low carb as possible, and I had a whole 2 days off plan in July when I went to Wimbledon. So I've not stuck to it 100% but all my "cheats" have been planned in advance (which I always think is better than spur of the moment eating) and I get straight back on track. I find it easy getting back into it, but I know not everyone finds the same.
I'd really consider moving to step 2 or 3, even if it's just a temporary change to give you a break from SS+. If you're feeling happy and don't mind losing slower you'll probably love it, and from what other's have said I think you can still expect to lose 2-3lb per week. Don't give in, you've done so well!! x