It is suggested by medical professionals that 10% drops in dosage should provide minimal if not any signifiant physical symptoms, the battle is the pysciological factor which is your brain telling you that you need more when really you don't.
If you wanted, you could drag it out 2 months, going 15/16 a pound, 14/16 a pound, etc each 5 days, 10 days, etc.
Honestly it depends on your desire to quit and your motivation level, resources of support around you, etc.
You need to ask yourself, are you really done with this shit? have you had enough of it? because I've gotten sober knowing I would go back and it was stupid as hell.