Hello. Acid rebound is normal when weaning off PPIs. Many people have to back up and wean off slower when pain from acid rebound is too great. The article link below discusses how to wean off PPIs. The areas that might be of most help are the "Weaning Process" and "The 5R Program for Lifestyle Modification" The 5Rs are remove, replace, repopulate, repair and rebalance.
Remove heartburn triggers. You seem to be doing some of the things like eating bland, eating more frequently and not eating before meals. The wedge should be helping too.
Replace missing vitamins, minerals, and nutrients.
Repopulate healthy intestinal bacteria with probiotics and prebiotics.
Repair the mucous membrane of your gastrointestinal tract with mucilage like aloe vera and your DGL.
Rebalance the body through stress management and exercise.
Hope the article and your doctor can help you past this. It's no fun. I've been there.
http://howtotreatheartburn.com/how-to-wean-off-ppis-and-why/