Migrations from SBS2003 exchange to hosted exchange cleanup

We have migrated some customers from SBS 2003 to third party non 365 hosted exchange accounts. What is still present is the original sbs outlook configuration. We have multiple networks that have some issues.
One network was migrated due to an AD failure. We had to do an AD restore form a corrupt backup with the assistance of a third party contractor. He was able to rebuild AD in a server 2008 environment, however there are still occasional references to the old SBS, particularly regarding folder redirection, but that has been cleaned up.
We still have issues with this network and some other post sbs 2003 networks where new client setups obtain the outlook configuration for the old sbs.
The network we are currently dealing with is mid migration to a 2008 domain. We migrated the email to the hosted Exchange friday and are doing client cleanups now.
We have our autodiscover A record entry present and new mobile clients have no issue configuring.
The outlook environment is a mix of clients from 2003 to 2013.
We can create a new mail profile and configure the clients without incident. However local archives require a manual spf export/import.
There is a PRF present on the SBS and in the C:\Program Files)\Microsoft Windows Small Business Server\Clients on the client machines
C:\Program Files (x86)\Microsoft Windows Small Business Server\Clients\sbsclientapps.log shows that the setup.exe that runs as part of the sbs login script is still apparently trying to reconfigure outlook using the sbs2003 deployment configuration

I have found multiple references to issues when migrating out of sbs2003 to hosted exchange and end users having issues with clients still trying to use the sbs or reconfiguring.

In and ideal environment we would be able to cleanup AD and remove all references to the SBS regarding exchange and client configurations, however I have been unable to find any clear guide or MS article.

We are well aware that it is cleaner in the long run just to wipe a domain and restart new, but that is not an option.

Any advice would be greatly appreciated in clearing out the sbs references for outlook.

Ideally we would make the change and push them out via GPO or script to clean up the outlook profiles without recreating new ones.

One big issue is the client machines to which multiple users occasionally log on. When they access an older cached profile they will still have the original outlook profile.

Using ADSI edit I see many references to the old exchange server, but it is outside my scope to begin making alterations as I do not know what the long term impact is.

This particular network state is pending SBS demotion and removal, I just want to clear up any issues before we dont have the SBS to reference anymore (as would have been very handy when we were clearing up the folder redirection on the first network mentioned)