I’ve seen the same “issue” with PUT I did the same and didn’t worry about it, as it fitting in nicely with my abstraction. PUT can be a toss up in HTTP parlance as generally you would be PUTting data in the body rather than just “query string” as is the case here. (I’ve not looked into it but it could be a hiccup in Nginx itself strokes beard thoughtfully)
Regarding 13a, there is no where to go and have a look, but I have read elsewhere that if there is a issue with your application that violates 13a they’ll get in contact fairly quickly. Just make sure you are not hammering too often too hard and caching where you can.
Really if you think you are hitting too hard to violate, you need to reassess your applications behaviour.