How long to reload a cannon?

[Sasuga]

https://www.d20pfsrd.com/gamemastering/other-rules/siege-engines/3rd-party- publishers/adamant-entertainment/siege-engine-ship-s-cannon/

According to the SRD, it takes 2 full-rounds to clean and load a cannon. But then it says it also takes 2 full-rounds to prepare the ammo.

Huh? What's there to prepare? They're not smithing cannon balls on the deck of a ship, and I suspect it would take more than 2 full-rounds to smith a cannon ball.

So, what does it mean it takes 2 full-rounds to prepare the ammo?

As I understand the classic cannon, you swabbed it after it fired to clean out the soot and any embers that might prematurely fire the thing when you add gunpowder, then you add gunpowder, then you might add some cloth in there, pack the whole thing down, then jam a cannon ball inside and pack it in, and then aim, light and boom!

But after you've added the gunpowder, the cloth, and the cannon ball (and jammed it all down properly) it's loaded. So that should be the end of the two rounds, right?

Clean: 1st round.
Swab; Powder; Cloth; Ball; 2nd round.

So what does it mean "prepare the ammo" and I wonder not only for my sanity, but also because can the ammo be being prepared (I mean, I'm still confused just saying this) while the cannon's being cleaned and loaded (by a second set of people).

How quickly can a cannon be loaded with enough people?

[QuidEst]

It's a third-party book written in 2009 or 2010- allegedly the first third-party release for Pathfinder 1e. The answer to "why are these mechanics weird?" is "because they were written by people trying to release a 192 page APG before the APG was out."

D20pfsrd is full of any third-party material that the publishers are willing to provide for free, which has a spread of quality and conditions under which it was written and published. Great if you want lots of options, less so if questions of cannonball preparation keep you up at night. (Aonprd.com has just the first-party rules if that's what you want.)

PF1's canon cannons don't separate ammunition preparation and loading; they just have a number of rounds of work by a full crew until the cannon is loaded and ready to fire again (which can be reduced by certain feats).