Adding additional mailstore

[roger_efn]

When adding a new mailstore, I'd like to be sure accessing accounts on that server work properly before putting it in a production.
I'm assuming If I set these attributes to False, I could set a couple of accounts on that store, but it won't be part of the rest of the system as far as logins go? I have a couple of other mail stores, I'm in the process of retiring them, but need to test account access first.

zimbraReverseProxyAvailableLookupTargets
zimbraReverseProxyUpstreamEwsServers
zimbraReverseProxyUpstreamLoginServers