Last
As always, test these updates in a lab first! I recommend checking out this 7-part guide on configuring Exchange in your lab. It doesn’t take much to get one going.
The updates are as follows:

Exchange 2019 Cumulative Update 8 | KB4588885

Exchange 2016 Cumulative Update 19 | KB4588884 | UM Language Pack

Exchange 2013 December Security Patch | KB4593466

Exchange 2010 SP3 Rollup 31 | KB4593467
Exchange 2016 entered extended support on October 14th
Back in October, Exchange 2016 entered extended support. The March 2021 cumulative update (CU20) is the last planned feature update for Exchange 2016. Any cumulative update after 20 is at Microsoft’s discretion.
Security patches will continue to be available in extended support until October 14th, 2025, delivered primarily through the Security Update Guide.
[Read more…] about Exchange Server Cumulative Updates (December 2020)