My only other Leap Year/Knitting postcard is this one by the Winsch company, which published cards from 1910 to 1915. Only one Leap Year falls within that period, 1912.
The Winsch company was based in Stapleton, New York and their cards are known for their high quality artwork and printing. Generally, their Leap Year cards are relatively common and inexpensive. Winch cards are instantly recognizable by the lion and squares on the backmark.
This particular card comes from a series designed to imitate the more expensive leather post cards of the period. They were illustrated by the artist Ryan and titled "Leap Year Etiquette." Each card in the series has a piece of etiquette advice, but with the genders reversed in a nod to Leap Year customs. My favorite advises that "Any woman who will chew tobacco in the presence of a gentleman brands herself thereby as a 'roughneck.'"