I definitely think they have been stalling to hear the outcome of this. The arguments the government's barrister made in court were the ones coming from backbench TRA Labour MPs (such as mine - something about case by case, most marginalised demographic ever blah blah), so if the JR dismisses these, then they really cannot justify continuing to sit on the guidance.
The outcome tomorrow is really important to try and get some progress on this, so I hope it goes the way we want.