This event began 01/15/2019 and repeats every year forever
On this day, January 15th, in 1986, version 1.35 of ADCM BBS is released. Version 1.0 was released sometime in 1985 (source: The Atari 8-bit Frequently Asked Questions by Michael Current). The ADCM BBS was written for the ADCM Pocket Modem. The BBS includes a command driven interface, private and public messages, file transfers, support for up to 255 users, and supports up to 500 baud. More information and images are available here.