Characteristics and Variant issues missing one

I am having a real strange issue with Characteristics and variants and for the life of me I am unable to figure out what is going on.

I created a test product (a bottle of hot sauce) and I also created a new characteristics for it where the customer can choose between purchasing 1,2,3 or 12 bottles.
from 1 to 3 bottles the price is fixed at $10 each but with 12 bottles the price goes down to $8.35 ea.

I set it up and it worked very well. The price was spot on and the weight seemed to be OK as well.

Then I got sidetracked and got logged out. When I came back the 12 bottle option was missing from the product, yet it is still visible in the administration.
This has been happening off and on, but until now I didn't know the system we'll enough to be able to know if it was something I did by mistake.

I took some screenshopts to show what I mean:

This is the product administration. Note there are 4 items including the 12 bottles one:

This is how the product looks in the front end. Only 3 values are displayed.



This below is the Characteristics screen you can reach from the product backend



Finally, this is the manage variants screen:



I also want to note that this same thing has been happening off and on. In the "manage variants screen" the prices are set for each product variant, but only on product has it. Yesterday of 4 variants 3 had iot but one didn't, even though inside they all do.

I am baffled by this. Now I have a good idea on how to setup characteristics, but I am afraid that there could be a bug that could create a big issue.

I'd really appreciate some help with this. Maybe I am overlooking something.

Thank you.

Interestingly, while still trying to figure out what is going on, I selected the "2 bottles" variant which should returnm a 2 quantity in the product quantity box. Instead, this is what it does:

Clearly, some confusion is happening here and I cannot figure out what it is

However, it l;ooks like I found the culprit. While reading the manual I found this:

If you have troubles with the display of variants of a product on the front end, you should:
1. Delete all the variants of the product on the listing of variants that you can access via the button "manage variants" on the product edition screen.
2. Delete the characteristics of the product.
3. Save the product.
4. Add the characteristics again.
5. The system will regenerate all the variants automatically and you should be able to see the dropdowns properly on the front end.

Which is exactly what I think is going on with my tests.

Still if someone knows of a good place to review the variants/characteristic workflow, I'd appreciate it.