OleOle
A southwesterly course like on the leg NILAM -> POVUS could be consistent with the BFO as well.
That works for me.
Although I can't stop myself from thinking that maybe the 18:22 location was really 6° 0'0.02"N 97°30'0.05"E and the plane flew along the FIR boundary to POVUS from there. Could your BFO numbers support that theory?