What's the meaning of the letter in the engine model?

[MrMoose]

When looking up parts on the Yamaha site, you first select the year of the boat, and then you select the model.
Here's my question. When selecting the model, I noticed that the model numbers are very similar except for a few letters. I'll use the 2015 AR240 as an example. There are 6 models in the listing. Three of them are low emission California models that have "LP" in their model number. The other 3 are non-California and don't have the LP designation. Both the California and the non-California model groups each have 3 different model numbers that are differentiated by the letters A, B, or C.
My question is, does anybody know what the A, B, and C signify?
SAT1800AP, SAT1800BP, SAT1800CP

Similarly, the 19 and 21 foot models seem to have A, and B designations, the SX240 has D, E, and F designations, and the 242LS model has G, H, and K designations.
Here's a pic:

 

[Andy S]

When looking up parts on the Yamaha site, you first select the year of the boat, and then you select the model.
Here's my question. When selecting the model, I noticed that the model numbers are very similar except for a few letters. I'll use the 2015 AR240 as an example. There are 6 models in the listing. Three of them are low emission California models that have "LP" in their model number. The other 3 are non-California and don't have the LP designation. Both the California and the non-California model groups each have 3 different model numbers that are differentiated by the letters A, B, or C.
My question is, does anybody know what the A, B, and C signify?
SAT1800AP, SAT1800BP, SAT1800CP

Similarly, the 19 and 21 foot models seem to have A, and B designations, the SX240 has D, E, and F designations, and the 242LS model has G, H, and K designations.
Here's a pic:
View attachment 47835

Typically that means the hull color/graphics package.