I don't think the rulebook adequately explains how replacements work. At least I can't figure it out.
On the production screen there are three numbers for every replacement unit type per nationality.
Top=Numbers of elements/hits that need replacing. (Sometimes in Red with exclamation points, sometimes in grey?)
Bottom=Number of Replacements ready to go.
Bot in Parantheses= Number of Replacements you have requested (bought) this turn.
Seems straightforward, but what is it exactly that you are buying? Do you have to buy 1 replacement per element/hit lost? Or is there something else going on here? I suspect there's more to it than that, but haven't been able to decide what it is.
Any help appreciated!