In THIS VIDEOAt 2:10, you see the Light blue armoured spartan, speculated to be Kelly-087. This Thread for more information
Kelly is the leader of Blue team, therefore, when the match starts and you’re blue, Kelly announces the gametype, multikills etc. Completly removing Jeff as the old announcer. The other spartans, leaders of respective team colours would do the same thing for whatever colour team you’re on.
If they post another question board, I’ll see if I can get this question in.