Using registry lists from Memory Alpha, and two different dating styles (when applicable), here's a fuller calendar of all the registries that can be converted to days:
January 5th - Antares Day (European style)
January 17th - Enterprise Day
January 28th - Fortunate Day
February 4th - Heart of Gold Day (European style)
February 6th - Oberth Day (European style)
February 7th - Sarajevo Day (US style)
February 19th - Yosemite Day
February 21st - Sherlock Holmes Day
March 16th - Bonestell Day
March 17th - Essex Day (173) & Hood Day (1703)
March 25th - Woden Day
March 26th - Franklin Day
March 30th - Yorkshire Day & Enterprise XCV Day
April 2nd - Heart of Gold Day (US style)
April 10th - T'Plana-Hath Day (European style)
April 14th - Alka-Selsior Day
May 1st - Antares Day (US style)
May 13th - Yamato Day
May 14th - Kelvin Day
June 2nd - Oberth Day (US style)
June 17th - Horizon Day
June 21st - Columbia Day
July 2nd - Sarajevo Day (European style)
July 18th - Biddeford Day
July 21st - Salcombe Day
August 15th - Hiawatha Day
September 13th - Gagarin Day
September 17th - Lexington Day
October 4th - T'Plana-Hath Day (US style)
October 17th - Constellation Day (1017) & Kongo Day (1710)
October 19th - Stamets Day
October 20th - Jenolan Day & Nash Day
October 22nd - Kobayashi Maru Day
October 24th - Whorfin Day
October 30th - Glenn Day
October 31st - Discovery Day
December 27th - Shenzhou Day