Need An Explanation Of The Sequence Of The Cancels On Train Trial Run Cover

I don't understand the cancels on this cover commemorating an Union Pacific 1934 train trial run from Los Angeles to New York City.

According to internet information, the run started October 22, 1934 in Los Angeles and ended October 25 1934 in New York City. The train set a speed record of 56 hr 57 mins

I first thought that the cover was post marked in NYC on Oct 25, 1934 for a return trip. But on the reverse there are two cancels from Los Angeles on Oct 23, 1934. My thinking then was that the envelope was not faced properly for two runs through the canceler when it was canceled in Los Angeles, and sent on without canceling the stamp, the uncanceled stamp caught caught by a clerk in NYC and run through a canceler there which produced the Oct 25, 1934 cancel.

However, that does not explain how this cover received an Oct 23, cancel in Los Angeles rather than the start of the run date Oct 22.

Can someone clarify what happened with the cancellations on this cover?

Thanks

Don Sellos

Here is another, also involving Mr. Richmond, currently for sale on ebay:
https://www.ebay.ca/itm/335132974334

Same dating. Different NY post office.