Like listing “6A” for the CC + FET driver of my S21E with 519a?
From the excellent review of S21E here by @bilakos10, I found out what the listing above means. This driver is FET+1(7135). Turbo is indeed FET, and max current of FET Turbo at 4.2v is 6A.
So exactly as per thefreeman’s note, a max current listing from Simon, like 20A for M21K, doesn’t narrow down whether it’s Buck or FET.