Why do you assume I’m doing this inside Excel? I was importing a data sheet into other software. By the time I got my hands on the data, it was an object of the sort {A: [/*data*/], AA: [/*data*/], B: [/*data*/]}. I had to sort the keys for presentation purposes.

In retrospect, sure, there would’ve been easier ways. But at the time I wasn’t aware yet that converting Excel columns to numeric indices isn’t as straightforward as a simple base conversion (like, e.g. from hex to decimal).