Drafts are 25 rounds unless specifically changed to more. You should be able to go to 28 man rosters now unless your front office page shows a waiver draft date..usually 2 days after initial draft. Then you would have a waiver draft shown at 5pm that day. Your owners would then need to fill out waiver draft lists before then. After the waiver draft all players would be free agents and you should be able to each own 28.
Usually, it's first come first serve after the draft ends. Unless it's a SLOW live draft, which normally has waivers. You can carry up to 28 without a drop, as long as you stay below the salary cap.
adstevens, If your front office page shows you have a waiver draft. go to the "your team" section along the top..in the drop down menu it would say waivers, click on that. That would take you to a new page which gives you a form to select players you want to draft, who to drop if you get them (if any) and at the bottom-waiver order for the league.