L4T Ubuntu and Atmosphere on same SD card?

I've set up Atmosphere and L4T Ubuntu on separate SD cards which works fine, but I'd like to keep everything on a single SD card and boot between them with Hekate. Right now, I have a boot partition (FAT32), L4T Ubuntu partition (EXT4), Atmosphere SD partition (exFAT), and a Linux Swap partition at the end. When I launch L4T Ubuntu from the main boot partition, it loads from the separate EXT4 partition, but is there a way to have Atmosphere load a specific partition through the ini configuration or patch? It looks like everything in the ini configurations points to files on the same partition and can't specify other partitions.

Pretty much everything I've found for Atmosphere partitions is setting up partitions for emuMMC which I can always try later, but mainly I just want a large SD partition in Horizon and don't need emuMMC at the moment. Does the Atmosphere SD partition need to be the first partition on the SD card then? The L4T Ubuntu boot rom can use multiple partitions, but maybe it's not possible for Atmosphere to use other SD partitions without patches. If this is the case, I can always resize my partitions with gparted or something. I just thought it was better to isolate everything to separate partitions.

On a somewhat unrelated note, I may switch my Atmosphere SD partition back to FAT32 for homebrew stability, but the 2 GB file size limit is annoying and homebrew has been running pretty well for me so far.