Would be a waste effort to try and overturn en bank when only 4 of the 11 judges were appointed by a Republican and the one appointed by Bush was on the original panel. That being said if the strategy is to stretch out the litigation so the Supreme Court opinion will be later, ok. But I think the faster the Supremes can dispose of the persecution of these nonsense cases the better.
Yes, it's all about stalling. Which is pretty indicative of how Trump thinks both the Supreme Court will rule and what the verdict of the trial will be, otherwise he would not have made this immunity claim to begin with nor been opposed to Jack Smith asking for a speedy Supreme Court expediated ruling.