Smoke and Illumination ammunition

[Blackcloud6]

How about this:

The resultant number is the number of turns that EACH smoke/illumination capable artillery unit can fire the special ammunition in the entire scenario. Note that the number turn is total for each artillery unit, it could fire 1 smoke and 1 illumination, or 2 smoke, or 2 illumination.

Pleas confirm the latter notion on total amounts is correct; this is how I read 17.18 to mean.