It was just the date on the article 1 May 21 instead of May 1, 21, following military and EU protocol. Gotta admit there hasn’t been much going on here. In measuring I often set my caliper to metric because it’s easier to calculate but we have a whole lot of existing structures that don’t fit metric and not worth the 100 years to convert. Ever buy gas in Canada with liters or Imperial gallons or liters in Europe and try and convert the cost? I’ll stick with gallons.
So I was working on a piece of equipment and checked one of the bolts and it was 9/16, so grabbed my SAE sockets. Then discovered that none of the other bolts fit the SAE, so went back to get the metric sockets and wrenches. Just a little irritating is all realizing 9/16th has a metric equivalent. It’s great for socket salespeople, but then the ratchets themselves are still 1/4, 1/2, and 3/4 and all the holes in the metric sockets are SAE.