Ok, so I had a bunch of DC8-55's on order, but then the DC8-61 launched in GW1, so I decided i'd cancel about 20 or so of my 55's (which spanned in delivery from late '66 to the end of '67). I then ordered DC8-61's immediatly after that and it skipped deliveries for all of '66. The production slots were showing my cancelled orders in grey, so it stands to reason that the production allocation system beleived that I still "had" those slots, which is not at all accurate.
I know the "cancelled order" grey box is to increase fairness for bankruptcies for alliance coordination purposes, but there's no reason that someone can't re-order immediately if the line is wide open like it is.
I've gone ahead and cancelled my -61 orders that ended up in '67 and I'll wait to re-order, but this is a terrible waste of $30 million and a terrible game play mechanic.