Metallic taste on first bag of new shipment

Has anyone else gotten a metallic taste from jimmyjoy-plennyshake? The first bag of every new shipment gives me a strange reaction with a metallic taste after about 2 seconds. It’s happened with strawberry, banana, and now vanilla. My GF doesn’t seem to have the same reaction (from the same bag). Could there be some scientific reason?

I’m a diabetic, and recently had bloods done, which were all okay/normal. The reactions tend to stop after about three meals, almost like my mouth has to adjust to the new shipment. Anyone else in the same boat?
[Edit] just to clarify, aside from the first day of each new shipment, jimmyjoy-plennyshake tastes fine. I’m also not ruling out coincidence, I’ve only had three shipments since starting 2 months ago, but I can’t think of anything else that would be a factor.

My apologies for the late reply! How odd this occurs just at every first few sips. If it’s a bad batch it would probably last longer, but it indeed sounds like it might be something you’re sensitive to instead of the bags being off… perhaps try asking your doctor for advice?