I would like to compute the range based on the high compared to the prior close. My data:

upstP = FinancialData["UPST", {2021}];
upstH = FinancialData["UPST", "High", {2021}];
upstL = FinancialData["UPST", "Low", {2021}];
upstC = FinancialData["UPST", "Close", {2021}];

I tried DatePlus[] without success

DatePlus[upstC, -1]
upstC[[1, 1]] // Normal // Short
DatePlus[upstC[[All, 1]], -1, "Day"]

I tried TimeSeriesShift[] without success

TimeSeriesThread[{1, -1} . # &, {upstC, TimeSeriesShift[upstC, -1]}] //
   Normal // Short

and some other variations that I can no longer remember. How would I subtract yesterday's close from today's high -- continuous???