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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 3 (VLSC)| KB4514141

Exchange 2016 Cumulative Update 14 | KB4514140 | UM Language Pack

Exchange 2010 SP3 Rollup 29 | KB4509410 (Released in July)
Exchange 2010 support extended
In a recent blog post, the Exchange Team announced that is was extending support for Exchange 2010 by nine months. Exchange 2010 now shares the same end-of-life date as Office 2010 and SharePoint 2010, which is October 13th, 2020.
While this extension allows for a little more breathing room, it does not extend support for Windows Server 2008 R2, which is the underlying operating system for many Exchange 2010 installations. Server 2008 R2 will still go end of life on January 14th, 2020.
The Exchange Team has provided this extension to allow companies more time to migrate to a newer email platform, such as Office 365, or, Exchange 2016.
Unfortunately, there is no direct path to Exchange 2019 from 2010. If you do plan to stay on-prem, you will need to migrate to either 2013 or 2016 (I’d recommend 2016 as 2013 is now in extended support). From there you can migrate to 2019.
For more information on migrating from Exchange 2010 to 2016, check out this recent blog article from the Exchange Team: Exchange On-Premises Best Practices for Migrations from 2010 to 2016
So, what’s new in these Cumulative Updates?
In this series of cumulative updates, Microsoft has resolved a number of security and non-security issues. You can read more about those in KBs 4514141 and 4514140. In addition, this set of cumulative updates addresses changes to daylight savings.
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