I want to create a RM9 tree that will be a reference copy of my Ancestry Tree without needing to approve changes

I have an Ancestry tree that I would like to download and keep updated automatically so I have an offline copy of all the sources and media on my tree which I would lose access to if I cancelled my subscription. It will be a reference only tree with a one way data download from Ancestry. Is there a way to accept all the changes without having to review each record I add or edit in Ancestry? In RM 8 I would periodically delete the tree and create a new copy but with a large tree that takes a long time (everything has to be replaced and then uploaded to my OneDrive).

For historical reasons I have a separate master tree (currently in RM7) as I do not like the way that the interface between Ancestry and RM placed data into fields, there seemed to be a lot of corruption due to a mismatch between field definitions. I also have a lot of sensitive data that I do not want linked to an online tree and cannot easily be filtered. This is the tree I would be editing and adding to, using information found on Ancestry/Findmypast/FamilySearch but placed into fields in a controlled way.

You can’t automatically update either from RM to Ancestry or vice versa. All updates are a manual process requiring approving each change.

You certainly could continue downloading the whole tree periodically with RM9 as you did with RM8. For long and slow things like that, I usually just initiate them when I go to bed and check on them the next morning.