My experience updating to WD OS 5 on my PR4100

About 3 weeks ago I bit the bullet and began the update to OS 5 ver. 5.18.117. I had a full backup of my unit prior to doing the update. I did not do a manual update but instead clicked the window on the control panel with the existing OS 3 version where it indicated an update was available. The update began and installed. The PR4100 stalled with the rebooting window showing. After a few minutes i began trying to access the unit with no luck. The control panel would not reload nor was the unit viewable on my MAC desktop. I did the recommended reboot of my router and the PR4100. I might add that you should not only shut down the PR4100, YOU SHOULD UNPLUG IT ALSO for about 30 seconds. Then once everything rebooted I was relieved to be able to open the control panel and access the PR4100, all files visible. However I was not able to create a new account for OS 5 using my previous email.
I tried several times and kept getting error messages. I decided to create the new account using a different email and was successful getting the account set up. I could then access the PR4100 online.
Then the indexing began. I have probably 15,000 + pictures and over 1000 video files all totaling about 7Tb of storage on a 16Tb Pr4100 Raid 5- 4bay unit. I’m running MAC OS 10.15.7
The indexing took overnight and then the preview creation began for the video files taking around another day or so. Finally I wanted to do another backup and discovered the OS 5 wanted to do it’s own clean backup. It wouldn’t use my existing backup from my OS 3 version software. That took a while and then the OS 5 version began another round of indexing and preview creation that took another day or so. Overall, the update was smooth after I got my access back after the unplug and reboot process. I’m happy with the operation of OS 5. It seems much faster than OS 3 in remotely accessing the PR4100 and the picture thumbnails are larger so you can actually see what you are looking for. I don’t miss anything in regard to the file size limitation for remote uploads as I don’t have any need to upload that size file. And so far I have not found that the few other limitations compared to OS 3 an issue.