Running two MECM implementations side by side - thoughts?

[PaulKlerkx]

Basics

• We currently have a CM2203 server that was implemented about 9-10 years ago with all workloads with MECM, cloud attached with a CMG.  
• our fleet is all Win10
• There are some minor issues with the server that we (and MS support) over the years haven't been able to resolve and several other things we want to change.  
• For the move to W11, we want to start fresh, we expect the process to get to W11 to take around 18 months. 
• We only have around 1800 endpoints to manage.  

The plan

• Keep everything we have in place to maintain our W10 devices till we have everything on W11
• configure a second server / site with all workloads in cloud to service Win11 devices. 
• Rebuild any device that is W11 capable to run on the new site. Set up autopilot for new devices. 
• No migration, all freshly created W11 applications/packages etc.  
• we currently use MECM/WSUS for updates - opinions on changing to Autopatch or WUfB? 

1. Any Tips?
2. Any problems you can see we should review before starting?

(sounds like a scenario off a MS exam :) )

[#2]

must be a bit too left field - 5 months, 168 views and no responses. :)

[#3]

There are no problems do this. However you do have to watch out for boundaries issues. e.g. site assignment.

BTW, I have at least 6 CM labs all within the same AD/IP range. You just have to understand what it means for you. I'm running out the door but I will try to see if you need more details tomorrow, when I'm back at my desk.

[#4]

@Garth-MVP Awesome, thanks for the response Garth.  I think, since posting, I think we have a decent grasp of what will be required, I was just after input on any gotchas to this scenario people had seen.  

If you have any insights into the move from WSUS, that would help too as this is all still a bit vague from what I have seen - Autopatch or WuFB or WSUS with CMG (what we do now) or just turn on windows updates (MS updates don't seem to have anywhere near the number of issues they used to have). 

What do people see as the most pain free, successful option with a lot of mobile windows devices that may not connect to the corporate network regularly.