HT to DRAGO. Eight F-15SGs have been assigned FAA N numbers recently on Aug. 6. The USAF serial numbers does not match to any F-15SGs that Singapore bought in 2005 or 2007.
N-number USAF serial number
N361SG 05-8361
N363SG 05-8363
N366SG 05-8366
N368SG 05-8368
N373SG 05-8373
N376SG 05-8376
N378SG 05-8378
N837SG 05-8371