It seems to me that LC4 key is essentially equivalent to RC4 state and thus RC4 early keystream bias does not apply as there is no key-expansion phase. Edit to

It seems to me that LC4 key is essentially equivalent to RC4 state and thus RC4 early keystream bias does not apply as there is no key-expansion phase. Edit to clarify: LC4 key has to be permutation of 36 elements, while RC4's state is bijection of 256 elements that is somehow construed from the byte-string key and the issue is in how this string->state transformation works (ie. you have to pump the function for >500 times to get unbiased output).