First Day Cover Question

I am not a dedicated FDC collector, but if encounter one with a stamp I like or is of topical interest I may get it. All the FDC's I have (about 45) have "FIRST DAY OF ISSUE" with 2 horizontal bars above and two below the text as the cancellation, except the Susan B. Anthony cover below. The envelope is postmarked Washington, DC August 26, 1936, which is the issue date for Scott 784.

My next oldest FDC is the 1 cent Franklin D. Roosevelt and Hyde Park (there are 4 stamps on the cover but not a corner block), Scott 930, issued July 26, 1945. It has the "FIRST DAY OF ISSUE" cancellation as described above.

Did they not use a "FIRST DAY OF ISSUE" cancellation until sometime after 1936 or could there be another intriguing explanation?

'
A piece of mail can be posted from the city where a stamp was first placed on sale, but travel thru the regular mail stream, in which case it will get the customary local postmark & whatever slogan cancel(s) they might be using on that day.

Cheers,

/s/ ikeyPikey (who does not know if that counts as intriguing)

According to the 2009 Scott/Mellone First Day Cover Catalogue and Checklist, "In the 1920s and 1930s, FDCs were canceled with everyday working postmarks. The post office first used an official FD postmark with the words 'First Day of Issue' in killer bars, for the 1937 Ordinance of 1787 commemorative (Scott 795). An official 'First Day of Issue' cancel has been supplied for almost every new issue since." (Mellone, pg 20A).

Thank you Walkman82. That is what I was assuming.

Sometimes enterprising collectors arranged to get first day of issue regular cancellations from cities other than the official first day of issue city - often with cities or towns that had some kind of tie-in with the stamp.