Although it is unlikely it seems much more likely then most of the theories going around atm (if that makes sense

).
The only four things that spring to mind: Plea deals are never off the table so to speak, so although the SA can remove an offer at the start of the trial there is always a possibility of re-instating it if the defense asks. Indeed, it is possible to make a agreement/"plea deal" after conviction in many US jurisdictions (if not all).
Secondly, it would be interesting if ICA was wanting to plead out since it is quite inconsistent with the sociopathy that people have suggested previously. Although, saying that, I suppose there was always a possibility for her to face reality and save herself.
Thirdly, there is no reason for JB to come off the case just because she is pleading guilty. Indeed, I view it as poor practice and unethical so to do. If the Client has admitted guilt and wants to plead guilty then she is quite entitled to do so.
Fourthly, I am unsure if there was anything to indicate that DP was likely. Although, perhaps the DT thought that it was a toss up between LWOP and DP and nothing else was going to happen.
But all in all a realistic possibility.