Well, the list of characters that are likely gonna be 4-A are:
1. Uryu (I'm expecting this to happen since he is "special" according to Kubo and also the fact we see him fighting Senjumaru in her own Bankai. That, and also since him and Ichigo's fight is likely to be extended in which he already blocked his True Shikai in the manga)
2. Jugram (if this 4-A Uryu ends up still fighting Jugram, he would scale to him, which with him being the grandmaster of the Quincies would make sense because he should be vastly superior to them.)
3. Lille (because of the draft, although likely to be an outlier)
4. Pernida (already a part of the Soul King)
And all characters who fought them (given there is an explanation as to why the hell these 6-A to 5-C captains just became 4-A, except maybe Kenpachi if Narita is within 3 miles of the draft room, then we know he just can for some reason. Otherwise, outliers.)