Package Import with Postprocessor - How to tell when all assets are imported

I’m importing a large package, and I need to do an operation after the entire package has been imported, but the postprocessor is called multiple times, each time with different portions of the package.

Is there any way to prevent this partial importing, or to detect that there are un-imported assets?

I haven’t found a way to do either of these things, but if you use the command line -importPackage option and nothing else, Unity will complete the import and exit. Then I can start it up again and do whatever I was going to do, and I know I’ve imported the whole thing.