Ok thanks! I am definitely going with the 24v then in a parallel connection. This helps a lot!That's because the 49.86Voc is determined at a controlled temperature of 25C. Voltage goes up when the temperature goes down. What are the winter lows at your location? On paper, those two panels in series would be 99.7V at 25C, but the voltage would go up to 112V on a frosty morning. You need a string calculator to determine it exactly.
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It looks like what I wrote above about using 2S2P would be incorrect for your particular panel. Two in series would go over the 100V limit in cold weather. Looks like the only way to wire them would be in parallel, two panels per controller. The Vmp is ~40-41V? That would be ~ 10A + 10A at 40-41V. Once transformed by the MPPT controller, your output for a 24V system would be 810W/25Vcharging = 32.5A. So, one 50A controller could work with two panels, at 24V. If instead you decided to go back to 12V, the numbers would be 810W/13Vcharging = 62A, more than the controller can handle.