From what I understand, positioning is to help the retina seal and to keep the gas from touching the cornea (causing cataracts). I was told on both of my surgeries that I could stop positioning when the bubble disappeared, but that thing can get really really small! Cal your doc and ask him. I know that positioning *****, but its worth it to really ensure that you don't have to go through more surgery!
Only your surgeon can answer that question
JCH MD