I sent a LOR, SASE, and a trading card to Matt Duchene of the Ottawa Senators on Nov. 13th 2017. I received my card back signed, along with another card also signed, on April 19th 2018. I used the Ottawa Senators address in the database:
Matt Duchene
c/o Ottawa Senators
Canadian Tire Centre
1000 Palladium Drive
Ottawa, ON
K2V 1A5