Graf Zep Worlds Fair Cover

Im recently going through my collection and did some research on the last US graf flight that occurred during the "century of progress" worlds fair in Chicago pertaining to this cover.



Apparently the graf made a short stop at the worlds fair (from its wiki):
While returning to Germany from Brazil in October 1933, the Graf Zeppelin stopped at Miami (NAS Opa Locka) and then in Akron, Ohio where it visited the Goodyear-Zeppelin Company's massive airdock before proceeding to the Century of Progress World's Fair in Chicago. After circling over the fair[N 5] and landing for a brief 25-minute visit there, the Graf then returned to Akron for two days before leaving for Friedrichshafen with an overnight stop in Sevilla, Spain.

I checked around and a good many graf covers are stamped from Akron where it was docked for days, but Im guessing there are few that came from the fair visit.

Also, it's kinda cool that FDR was forced into printing this stamp as to not cause an incident Hitler's Germany. However, FDR did mange to get the Nazi swastika removed from the blimp's tail on the stamp.