The gap between the first and second light is quite large at about 400ms or so. The gap between 2nd and 3rd is much tighter such that you only need to 'learn' the 2nd light timing. Just dont mash light like you might do with Orochi to guarantee the double top light as that will make you techable. But if youre landing Sickle Rain your opponent isnt any good so dont worry about it.