Question About Penn Yan Post Office

Apropos a discussion that occurred earlier on the "1890s Columbian Covers" thread, can anyone please tell me whether the Penn Yan, NY, post office would have been a carrier or non-carrier office in the 1890s? Penn Yan had a population in the mid-4000s then. I wonder if the cover shown is a 1st class drop usage (the presumption if Penn Yan is non-carrier office; otherwise it is 3rd class use, despite improper dated cancel):

Is the back flap unsealed? That's usually the best determinant of drop vs. 3rd class. Some annual postmaster general reports list carrier offices and you might be able to get a dispositive answer with some digging on google books.

Penn Yan, NY received city carrier service on April 1, 1898 (typo, meant 1899), per this announcement in Postal Bulletin # 5735, dated December 19, 1898:



The year date was corrected to "1899" and implementation delayed to July 1, 1899 in Postal Bulletin # 5762 dated January 21, 1899:

Thanks for responses. To paperhistory's query, I do not yet have the cover in question (just bought it on ebay) ...

In any case, many thanks to John Becker for the relevant info.

I did not know until today that the town name means Penn(sylvania) Yan(kee)!