There are a few discrepancies between documented usages of -t and -T options

Trivial usage message [1] implies -t exists and says:
//usage:       "[-sfnbtv] [-S SUF] TARGET... LINK|DIR"

but opt does not handle it [2]:
opts = getopt32(argv, "^" "sfnbS:vT" "\0" "-1", &suffix);

and web site command help does not list -T (nor -t)[3]:
ln

    ln [OPTIONS] TARGET... LINK|DIRECTORY

    Create a link LINK or DIRECTORY/TARGET to the specified TARGET(s)

    Options:

            -s      Make symlinks instead of hardlinks
            -f      Remove existing destination files
            -n      Don't dereference symlinks - treat like normal file
            -b      Make a backup of the target (if exists) before link operation
            -S suf  Use suffix instead of ~ when making backup files


[1] https://git.busybox.net/busybox/tree/coreutils/ln.c#n24
[2] https://git.busybox.net/busybox/tree/coreutils/ln.c#n64
[3] https://busybox.net/downloads/BusyBox.html