I found this information and I thought it was good to post it's something that some of  the long term sleevers have concerns about even some of the newbies have concerns about what if:

Weight regain after bariatric surgery can be an uncomfortable subject and one that both surgeons and patients want to avoid talking about, but can’t. To be sure, weight regain happens – the real question revolves around the cause. We understand that the choice to have weight loss surgery was a big one and the return of weight (in any amount) is disappointing. But understanding the way our bodies work and what may be behind the weight regain can help us address the issue more effectively.

First and foremost, don’t get down on yourself. In all likelihood, your surgery did work and you are doing the right things, but our bodies change. As our bodies change, so too do our needs.

Natural Regain: Some weight regain after bariatric surgery and especially gastric bypass is normal. If you regain 5-10% of your excess body weight after a few years of losing consistently, don’t fret. Speak to your surgeon, but it is likely no problem at all.

  Diet modification: Many of us tend to overdo it in our diets. It is tempting to over-diet, but the results can be counterproductive. Crash diets can even cause us to retain more fat than a diet of moderation. Be sure that you follow your diet plan closely and work with your dietician to ensure the very best results.

    Exercise habits: As with diets above, there is a fine line between good and bad exercise. Understanding the exercises to which your body responds and working with an exercise physiologist can help ensure that your exercises are doing good and not harm.

Pouch or stoma enlargement: The stomach pouch and/or stoma (the opening into the stomach) can in fact stretch over time. This can cause mild or significant weight regain and can be corrected with one of several simple outpatient procedures.

Revision Surgery can be effective, but ONLY as a last resort. Simple outpatient procedures and even major surgery can be used to revise an unsuccessful primary procedure. While revisions are generally effective, they do carry a higher risk of complications and all other solutions to the weight regain should be implemented before considering a revision procedure.