Direct Upgrade from SCCM 2012R2 SP1 to 1606 or higher (not via 1511 and then 1606)
Right now we're having an environment with a CAS and two PRI with 165,000 clients. The hardware is "old" and has to be replaced.
Everything is running on SCCM 2012 R2 SP1, SQL 2012 and windows server 2008 R2. Now we're planning an upgrade to SCCM 1606 or higher, SQL 2016 and windows server 2016 on different hardware. So far we found some TechNet pages telling us that there are issues with SCCM 1511 and SQL 2016, but SCCM 1606 and SQL 2016 ought to work (There is right now no information about the supportability of windows server 2016 with SCCM 2012 R2 SP1 or 1511).
If there were a direct upgrade possibility to SCCM 1606 (and not via 1511) it would be much easier for us to upgrade.
ConfigMgr 1606 was a baseline build. There will be future baseline builds from time to time.
so far I don't see a possible update scenario for our organization... Windows Server 2016 is only supportet by SCCM 1606++