Is there a medical reason you should wait 12 months after a sleeve gastrectomy before having plastic surgery?

I had VSG May, 2016. My BMI was relatively low at 32 at the time. I'm close to my goal weight of 150lbs. Currently at 5'5 159lbs. Most of the PS' I consulted indicated I would be fine to have a breast lift with implants and liposuction in December, 2016 as planned, if my weight has stabilized, but 2 indicated I should wait 12 months. Is there a reason for waiting or greater risk for not waiting? I did not get a clear reason from those who insisted I wait.