SCOTUS appoints counsel (and delays argument) after new government position on crack sentencing retroactivity issue in Terry

As noted in this prior post, earlier this week the Acting Solicitor General informed the US Supreme Court that the government had a new (pro-defendant) position in Terry v. United States, No. 20-5904, the SCOTUS case concerning which crack offenders have a so-called "covered offense" under Section 404 of the FIRST STEP Act to allow for their retroactive resentencing.  The Supreme Court yesterday responding via this order in the Terry case:

The case is removed from the calendar for the April 2021 argument session.  Adam K. Mortara, Esquire, of Chicago, Illinois, is invited to brief and argue this case, as amicus curiae, in support of the judgment below.  The case will be rescheduled for argument this Term.

In other words, the Court appointed a lawyer to make the case against broad retroactive resentencing for certain crack offenders after the government said it no longer supported that position.  Doing so is not unusual when the parties agree on an outcome different from the decision below.  What is relatively unusual is that this appointment needed to be made long after cert was granted and briefing complete because of the Acting SG's new position on the merits.

I am pretty sure, under normal circumstances, the April argument session is the last one of a usual SCOTUS Term. But in our current a world of online arguments and disrupted timelines, perhaps the Justices can and will schedule this one argument for some time in May.  The Acting SG noted that the defendant in this case is due to finish the imprisonment portion of his sentence this September, and it would seem the Court is remains eager to resolve this matter before it takes its summer break.

Prior related posts on Terry:

• SCOTUS grants cert on four new criminal cases, including one on FIRST STEP Act retroactivity of reduced crack sentences
• Federal defendant in Terry with many notable friends urging broad application of crack retroactivity provision of FIRST STEP Act
• Reviewing the still uncertain state, and the still certain need, for effective federal crack retroactivity resentencing 
• Acting SG tells SCOTUS that new administration now supports broad application of crack retroactivity provision of FIRST STEP Act in Terry