The closest I found when searching for Sausage Day was Oct 11th (according to https://www.daysoftheyear.com/days/sausage-pizza-day/).  I'm surprised that sausages don't have a day of their own.  I suppose anyone can designate a day for anything, and if enough people agree that it is that, then it is... 

 oops, that didn't copy-pasta correctly.  try this:

https://www.daysoftheyear.com/days/sausage-pizza-day/