Hello there,
I'm a System Administrator and Network Administrator working in Canada. I have just recently migrated a 300 employee facility off of Symantec Endpoint Protection and on to Sophos Endpoint Protection. I know everything to watch for, and the proper way of handling this. I will break down the project in to phases:
Phase 1: Information Gathering
During this phase we create an asset tracker with PC names and confirm if SEP is on each asset. We also track if the SEP console has these PC's monitored. We will use this information in the next phases. I will also learn about the AD structure for reference.
Phase 2: GPO Planning and Creation
During this phase we plan out the two needed GPO's for this project, on to remove the SEP and if necessary, on to install the new AV. I will then create a test OU and User and ensure these GPOs function.
Phase 3: Scheduling
Schedule the deployment, decide if done in batches or all at once.
Phase 4: Deployment
We deploy the GPO's on schedule and record users that still have the software, this phase can be tedious,
Phase 5: Cleanup
This stage involves cleaning up the left over Symantec notifications that can stick behind even after an intense uninstall, many companies don't expect this but I have personally encountered it.
Let me know if you would like some help.