Unfortunate outcome - EOTech 518 A65 Holographic Non-Night Vision Weapon Sight

I purchased this HWS from Optics Planet due to my many great purchase experiences with them. The transaction was as usual, all aspects and delivery were excellent. The problem with the site surfaced when the manufacturer, EOTech, made a public announcement that the HWS would not hold current zero for temperature extremes. This was announced AFTER my purchase, and was exactly what I had experienced on two outings to the firing range. I initially set the HWS for zero at one hundred yards, using a new Ruger GSR. Performance was outstanding, noting that the ambient temperature was 35F. When I returned three weeks later, the weapon was printing very small groups at the same distance, but the zero had shifted SIX INCHES to the left. The ambient temperature was 78F, and the shooting method from the bench was not deviated from in any way. I promptly verified this again, and at that point contacted EOTech for their offer of a return for full refund, plus shipping.
I would like to emphasize that this is in no way a reflection on Optics Planet; they continue to offer us outstanding service.