Idealogian

Thanks Reuven, that was really informative. But can you clarify that comment that said that people who only wait 3 hours should say a 3-hour selihot??!!! (Did he mean to say he doesn't consider the 3-hour wait to be acceptable?)

Not that it's not acceptable, but that both are, at least according to R' Schwab, uniquely Yekke (German Jewish) minhagim. So, if you're going to be a Yekke l'kula (regarding the leniency of waiting only 3 hours between milk and meat), you should be consistent and also be a Yekke l'chumra (regarding the stringency of saying extremely long s'lichot on erev Yom HaKippurim).

Sort of like saying that if you're going to eat kitniyot on Pesach, you should be saying s'lichot starting from Rosh Chodesh Elul.