|Hello Afihandarin san,|
Japanese F-15J upgrade program is called "F-15J Kai". "Kai" is a Japanese word which means "Modify". There are 2 types to upgrade, type-1 and type-2. 928 is a prototype for type-1, and 942 is for type-2. F-15J Kai have APG-63 (v)1 as its RADAR-FCS. It is not AESA, but seems can easy convert to (v)3 because it developed based on the APG-70.
This upgrade program is for MSHIP'ed F-15J. I'm not sure how many F-15J were upgraded now, but program is on going.
I hope this makes sence. :-)