Shaquana523 4 Posted April 9, 2015 So I have 1199 seiu insurance and I just completed everything on my pre op list including the 6 month supervised diet but I don't know how the approval process goes. I'm from New York and I will be having a gastric sleeve at Mount Sinai st luke's hospital. ....can someone who has 1199 seiu insurance let me know how long it takes them to approve your for surgery Share this post Link to post Share on other sites