Your initial Colon Cleanse should not last longer than 6 months...at most. Any cleanse should alternate cleansing with periods of rebuilding. At 6 months you may still be passing mucoid plaque. After taking a break from the initial cleanse you may need to do another cleanse...and another...and another. These subsequent 'rounds' of cleansing should only last a few months at a time and always be followed with periods of rebuilding. The amount of gunk accumulated varies for everyone so how many rounds will also vary. Remember that what comes out is greatly influenced by what goes in...if your diet is high in mucoid-forming foods (meat, dairy, sugar, flour products, etc.)...you may keep passing mucoid plaque whenever you do a cleanse.
But MOST IMPORTANT...always pay attention to how your body is responding to a cleanse and honor what it tells you. No cleansing...fasting, colon cleanses, liver flushes, etc...should ever be forced or based on an intellectual decision..."I must complete X number of days on the Master Cleanse!". Listen to your body... not your head!