How do Catholics in Japan celebrate the Feast of the Discovery of the Hidden Christians?

Most people know that March 17 is the Feast of St Patrick. But in Japan, the faithful celebrate the Feast of the Discovery of the Hidden Christians or Kakure Krishistans . In 1614, all Catholic missionaries were expelled from Japanese soil. Fr. B. Petitjean arrived in Nagasaki, Japan in August 1864 and was able to construct a small Church. On March 17, 1865 he discovered that the Christian faith had survived in Japan for some 250 years without any missionaries (priests) to administer the sacraments! Outside the celebration of the Mass for this [feast](https://en.m.wikipedia.org/wiki/General_Roman_Calendar) , how do Japanese Catholics celebrate this feast?