I have 2 P3's, a P3P and a P3A. Here's what I have observed through the last 3 firmware updates for each P3 as it relates to this issue. Maybe you're having the same problem and noticed this too. P3P Firmware 1.1.9 is when the horizon issue got bad. Nothing I did, all the recommendations, would fix it. Until I went to firmware 1.2.6. Remember that is the firmware that updates and the gimbal does some extreme movements towards the end of the update. But 1.2.6 introduced the VPS issue and for me a barometer hold steady height issue. I left it alone and waited for the next firmware release and flew the P3A instead. Firmware 1.3.2 comes along. It fixes VPS and the barometer issue but my off horizon is back. Nothing I do will set the horizon correctly. Remember 1.3.2 is a firmware update that doesn't do the extreme gimbal movements during the update like version 1.2.6. My thought here is that we need that more extreme calibration instead of the mini calibration that can be done in the Go App. I believe that calibration is what fixed my off horizon issue. P3A This bird has been rock solid. I bought it after the P3P. I left it at firmware 1.1.9 due to the VPS issue introduced in version 1.2.8. It's horizon has never been off. 1.3.2 comes along and I update from 1.1.9 to it, skipping 1.2.8. That update has the extreme gimbal calibration in it as I believe it encompasses what the 1.2.8 firmware would have done if I had upgraded to it. The horizon remained rock solid after the 1.3.2 update. Conclusion My P3P has a gimbal issue and it doesn't seem to be a firmware/software problem. I think if DJi provided the more extreme calibration it may be able to set the horizon back to a tolerance level that it could make up for. But it seems as though successive firmware updates that don't include that more extreme gimbal calibration resets the tolerance level to a point that my P3 cannot compensate for. So, I think I'm sending the P3P back to DJi while my gimbal is still covered under their 6 month gimbal warranty. I have the P3A to fly so it's really no lose from a flying standpoint.