I'd also tell him about the hernia for sure. I went back to my surgeon 7 years after my sleeve with severe hiatal hernia symptoms. He did an EGD, and as soon as I woke up told me he saw the hernia and had scheduled my revision surgery for the following week. Hernia and GERD are two very good reasons to revise to bypass as it should help with both.
As others have said though, don't expect as much weight loss with the revision as with the original surgery.
One other thought, I had great luck using my sleeve with a combination of time restricted feeding and keto. I only ate between noon and 6pm (lunch at noon, dinner by 6pm, no snacking) and generally followed keto guidelines. This is the insulin control diet regimen recommended by Dr. Jason Fung. I dropped 20 pounds in a couple months and found it was easy as since my sleeve I didn't have a great deal of hunger.