Sometimes I am logged out when I first get here or on other sites and have to log in. Because I don't normally log myself out. In case I go to a site several times a day. But I don't believe I've been logged out in the middle of doing something. Usually if weird things like that start happening, I reboot my computer. Same with my phone, it needs shut off and back on at least once a week. But it could totally be on their end too. If it keeps happening, I'd say log out before you even start anything, maybe clear out your temp files and cookies too. Send a help ticket if nothing you do helps. Good Luck!!