Yoda,
I find that I only have to do minimal manual update work, even when I'm using RB away from and Internet connection. If you use the same PC, say a laptop, both with the connection and then without this works well because the main source database NavData.db3 is auto populated when you are on line and then these details are available when you are next working off-line.
Obviously, if you get a new aircraft when you are off line, then you won't see all the details for it. Also, the records in MyLog - your detected aircraft - will have details missing. Every now and then, I use Populate in the MyLog Tools menu, this looks at the NavData database and also checks the Server if you are on-line to fill in any missing details.
If you are using different PC's, then just copy the NavData.db3 file from the Internet machine to the portable machine, and your source database will always be up to date. I think that the only time you will have many aircraft without details if if you take your RB to a different continent.