Info about N435TF comming from gulfstreamjets.blogspot :
5 of the 6 Gulfstream 4s operated by Saudia have recently been transferred to Jet Midwest, probably for parting out as the oldest is nearly 30 years old. HZ-AFU (1031) became N431TL, HZ-AFV (1035) to N435TF, HZ-AFX (1143) to N143PK, HZ-AFY (1166) to N166JM and HZ-MFL (1128) to N428BC. This just leaves HZ-AFW (1038). These have now been replaced by Falcon 7Xs.