All scheduled upcoming classes are published on the Flight Ops page on FlyingTogther (aka Skynet) under Hiring and Recalls. I think classes through Feb or Mar are currently listed as it's essentially a new class every Tuesday until summer.

Furloughees have first-come rights for any class with 30 days notice as inside of that they go to new-hires. There is an online form to accept recall with ones's desired date(s) and there is no limit to how far in advance one can pull the trigger as long as the class is announced.

Once you accept, they will send you some forms to fill out for background checks and you will need to take a drug test and submit copies of licenses (FAA & FCC) and medical prior to the first day.

The email addresses of the folks in charge are also available online and they are very responsive to questions.

Accepting is the easy part.....basic indoc in DEN and aircraft training in IAH is a total cluster fluff from a process, efficiency, or quality perspective. You would never guess that UAL and CAL have been flying airplanes and training pilots for 80+ years. If you remember what UAL indoc and training was like in '99-01 it will be quite shocking.