The drone started to "drift" about 1 second before it switched from Pano to Sport mode.
Prior to that drifting, the drone was at about an 8-11 degree angle (pitch) since it wasn't facing the wind at that point. After the mode switch, the pitch...
You mentioned that "the drone was limited in tilt, making it unable to fight the wind and hold position." However, that doesn't seem to be the case here, as the drone maintained its position just fine while tilted at the same angle before the...
Exactly where the drift starts, the tilt angel (combined pitch & roll) change from an earlier average of 14 degrees while holding position, to a rather constant tilt just a tad below 10 degrees. This seems to generate a drift reaching 5mph during...
It's an interesting observation, but I can't determine whether it's the cause or merely a coincidence. I suspect the drift was caused by a change in wind speed without the proper counter adjustment in tilt, but without knowing the exact wind...
If comparing the difference in IMU & GPS velocity during that whole Sport mode period between the end of the pano & RTH initiation, we see that the differences are nearly zero... this indicate that the FC very well knew that the drone was...