Howdy, Belter! Glad to hear you're getting on well enough to have questions about the biggest Beltin' Bird going. The Albatross can mount the largest Spares Bank available on the Belt, the 7-Slot Spares Bank (available at all reputable and less than reputable refit stations for 7 Cred).
Looking at the sheet, I'm seeing the confusion though. Each upgrade is indeed a mark on the Spare Bank Expansion category on the sheet. And we are looking at a weird number of bubbles on the bank itself. We'll get that sorted and polished once we're clear of space-plague. Play it as it lies for now, and we'll get it all ironed out.
Thanks for the extra eyes, Belter. This is why we're lucky to have y'all out there.