You don't see it spelled "grey" much anymore, at least not in the States?
Keen observation. I did know both were acceptable. I have been reading Wodehouse recently, maybe that explains my subconscious usage.
ChatGPT:
Grey and gray are both correct spellings of the same word, which means the color between black and white. The only difference is that **grey** is more common in **British English**, while **gray** is more common in **American English.