@Catica Also - his future SS pmts will never drop below what he is already getting at present. If the COLA is high enough for him to receive an increase that will be his new (increased) basic SS pmt.
In other words, even if his medicare Plan B premiums were to go up way above the COLA increase - his SS pmts would not go down, but remain as is.
A small consolation, but nevertheless, quite reassuring if your SS pmts are on the low side.