Does anyone know how to rank up in individual classes? My rank is still 0 for support and it's my main class. I've found mixed information on the Battlefield subreddit and don't feel like I'm making much progress.

Hmm that sounds pretty weird. You should level at least to level 1 in support just by playing the class for a couple of hours.

If you just started playing bf1 it could be that the servers are again acting up and not showing peoples ranks so it will look like everyone is rank 0.

@nardak: It looks like I'm really close. I read on Reddit that sometimes the game glitches and I should go to the customization screen in game and make sure the progress saves. Maybe that'll work.

You rank up each class doing class specific actions with assult its doing damage to armor, medic reviving and healing, support supplying ammo and recon sniping from distance or spotting. It is bugged though you only earn xp towards the first class you spawn as, swapping classes will prevent you earning xp even if you swap back. I'm max rank with each class so I'm sure as what degree Dice have fixed the bug, buts that was the deal at launch.

@thepanzini: Makes sense, thank you