For one week: I would keep your syns at 10 a day, vary your HEX Bs so you're having 7 different ones, measure your HEXs religiously, syn everything and check syns before you eat them, keep a food diary, try and drink 2.5lt water a day, and try doing a few Extra Easy days but having 2/3 of your plate with superfree foods and 1/3 red/green free food, mixed with a few red days.
See if that helps!
BTW - I've got a similar amount to lose as you to get to my target and I find the weeks where I do all red and vary my Bs are when I get the most losses (though I haven't tried the Extra Easy 2/3 to 1/3 yet which I will do if I reach a plateau).