This is their final response in their own federal district court. The district court will issue its decision. Afterwards the next appeal would be to the US Supreme Court. That level of appeal can take years if accepted, or more commonly, is ignored. In the meantime there can be orders for them to comply in the meantime or face consequences.
I thought we were at the step where the case is now fully briefed? Isn't the next step oral arguments at the district court level? Then a District court ruling. Then appeal to 9CA, and so forth. Although if someone files for an Emergency TRO, I'm not sure if that goes to 9CA or to the SCOTUS Justice that oversees 9CA (Kennedy).
The hearing at the district court level will be before a magistrate judge (because of the way that the issue arose in connection with a search warrant). Magistrate judges' orders can also be appealed to the district judge assigned to the case, which happens before an appeal to the court of appeals.
What can we expect to see from Apple? Would they comply, if not what consequences would we see them face? Fines or jail-time for those making the decision to not comply?