Mate, please stop talking about QC. QC is wasted, dead time. Inspecting good from bad, improves nothing. Quality ASSURANCE is upfront planning of design, processes and supply chain, to stop bad things happening. If your supplier let you down its because you chose the wrong supplier. Proper Production Engineering is not a waste of money or something that only other people do.
The honest thing to do would have been to email your customers, explain the situation and offer the other grill option. Copy and pasting 66 emails takes a couple of hours. My cab was late even with the other type of grill. Quoting inaccurate lead times makes a liar out of you and an enemy of your customers.
You would be amazed how people respond to timeliness and honesty.
I think this is a bit harsh on Alex, as a Barefaced cab owner I had to wait what seemed a lifetime (always does when you want something badly ) but in reality was not too long after the delivery date, as some say, the best things in life come to those who wait and believe me, these cabs are worth waiting for
I would rather wait a few months for the right product than regret buying a lesser product because of a short delivery time, I know I will be happy with my Super 12 for many years .