How to raise FFL and DFL from 2008R2 to 2012R2 with 2016 DC's in place!

Hello everyone and thank you as always in advance for your insights, etc. Much appreciated.
Situation: We have a FFL/DFL at 2008 R2 with two 2008 R2 DC in place. We are moving to two new 2016 DC shortly and once all DC's are 2016 (we are decommissioning the two 2008R2 once the two 2016 are okay). I was going to raise our FFL/DFL to 2016, but cannot do it since our virtual environment (VMware 6.0) will not work , is not supported, with FFL/DFL 2016 because of this https://kb.vmware.com/s/article/2071592 so I can only go to 2012R2. So the question is how does one raise the FFL/DFL from 2008R2 to 2012R2? Also is that process different from raising the FFL/DFL from 2008R2 to 2016 (just curious)? And does it make a difference that we have 2016 DC, but are only going to 2012R2 on the FFL/DFL (I am assuming that is okay). Finally, what rollback features are available in our scenario --> 2 x 2016 DC, 2008 R2 FFL and DFL that has been raised to 2012 R2 FFL and DFL? Cheers :-)