Is it a typical practice to bring in a different legal team if you appealed to the SCOTUS? I figured a legal team would jump at the chance to get that credit on their resume...unless they are extraordinarily humble and thought someone had a better chance.
Your job as an attorney is to do the best job for your client, and there are areas where you need a specialist. You don't have to drop off the case or the briefs, but it helps to have someone on board who the Court respects, and who knows what they're doing.
My brother went to MIT, but ended up getting his law degree after that when someone stole his IP (it was a university hospital in Boston, ahem) and he wanted to protect himself in the future. Even though he doesn't practice law now, they bring him in a lot for anything tech or software related.
You may know your substantive area of law (and the facts of your case) the best, but a SCOTUS specialist (a) knows how to argue to the Court, and (b) is smart enough (actually, I'd use "brilliant," usually) to learn most of the substantive stuff while relying on you when needed.
As an auditor, one of our standards is that if we feel we don't have the expertise to do something, we bring in someone who can or withdraw from the engagement. So, I appreciate the fiduciary responsibility to the client.
So there are people who specialize in it. They are generally very good.
We brought in Carter Phillips in a case I worked on. He was impressive.
I had a dear friend who was one of these. He was brilliant. I grieve his passing every day, but am also thankful he didn't live to see this court.
It used to be much more common for lawyers who handled a case in the lower courts to handle it before the Supreme Court, but increasingly litigants hire one of a handful of elite lawyers, almost all men, based on the probably correct belief that the Justices like them. It’s not great!
Or you discover that you hate appellate work (meeeeeeee.)