Fot 10/1 Likely Letters, recruited athletes generally need to have their full, completed ED application on file by September 30 (or earlier in September if the coach requires). So this date is earlier than the date non-recruits submit applications. While there may be school ) sport exceptions, there will be no LL without the application. And the LL comes from admissions, not the coaches.
So yes, you will need to determine which is your top choice in September. Don’t try to string along multiple coaches past that date; they all talk to each other, and won’t end well for you.
There are recruited athletes who do not apply ED, but they are the exception, and are invariably world-class with an Olympic medal in their safe deposit box. Assume you are not the exception.