Short answer, yes, you can split the contents of autoinstall.lst into many sections.
Longer answer: there was a discussion that covered this, but I’m not being able to find it.
But currently, Syn3Updater does exactly that to perform an autoinstall of MAPS in MY20 for latest EU and NA maps (not sure about ROW, and ANZ are locked).
You can get a sense of the syntax and context in this post, which is a tutorial for manual upgrade Tutorial: 2020 North America 2.20 Map Installation (Stand-Alone without Reformat) with Updated NAV_Voice 06/21/2021 via autoinstall.
Also, as said before, Syn3Updater already does this, so you could create an autoinstall configuration for MY20 EU and see the results.
If I find the other discussion I will update this thread.