I have completed the March 2020 update to my list of book festivals for those who find this a useful reference:

www.jacobmappel.virb.com/book-festivals

If you would like to have a book festival added, please feel free to email me at jacobmappel@gmail.com. And if you know the dates of one of the festivals listed without a date, please let me know that as well.

(Festivals should be open to all and targeted to the general public, as opposed to a niche audience, and should not charge admission.)