Frozone perhaps meant for Silver's previous promotion, before this one. "Late Congratulation" would be sufficed.
As Ultra mentioned; "Now we believe it the time for him to be promoted '''once more'''." - Perhaps that's what he was insisted to do.
Apologize if that's not what you're thinking - just wish to pull up to the date. That's all.
Support. He has done his job well as far as I see.