>>12450657 (pb)

>The SAM flight was a Gulfstream at 43K'

No it wasn't. It was at least a 727-sized plane. I'd say 737, IMO. Much larger than the Gulfstream SAM448.

I think what I saw (pic related) was not transmitting on ADS-B, which would explain why it isn't visible.

pic related: I seent it at 4:45 PM EST - looked to be over lakeland, flying pretty low (not nearly cruising altitude.) Maybe 10-15K ft?