The BBS Directory (new in 0.6.0) is a dialling directory of BBS systems. Open it with the BBS Directory button on the toolbar, or Tools → BBS Directory….
Press Update lists to download the Synchronet BBS List and the Telnet BBS Guide; lists are downloaded only when you press it, and the server is asked to send a list only if it has changed. The Synchronet list comes from the Kalgoorlie Retro BBS website (https://retro.theiguru.au/bbslist/synchronet.lst), refreshed daily from Synchronet's own BBS list with Telnet first; the Telnet BBS Guide comes from syncterm.bbsdev.net. Lists… changes, adds or removes list addresses (any list in the SyncTERM .lst format).
bbs-directory.json in the profile folder, and downloaded lists in bbs-lists/. Tools → New BBS session… and Tools → Import BBS list still work as before.
Synchronet BBSes share their BBS list with each other through Synchronet's list network, and each BBS records every way to connect (Telnet, SSH, RLogin and others). The copy of that list published for SyncTERM keeps one connection per BBS and puts SSH first, which needs an account on each BBS. The Kalgoorlie Retro BBS receives the same list every day, exports it with Synchronet's own sbbslist.js with Telnet first, and publishes it at https://retro.theiguru.au/bbslist/synchronet.lst (refreshed daily). Most BBSes therefore come in as Telnet, with the BBS's own login and new-user screens.