Its frustrating but keeping fingers crossed for you. I had sticky scales last week from tuesday weigh-in. Day after weigh in i was 3lbs lighter then nothing til the morningof my next weigh in when i'd lost another 2.
Its pretty impossible to put a figure on it, all you can do is give yourself the best chance. Just keep glugging the water and maybe a bit of gentle exercise, which might give your metabolism a bit of a kick
Good luck x