Q. Is it better to accept and begin Yom Kippur earlier (since Tosefes Yom Kippur, or the acceptance and adding to the day is a Biblical mitzva), or is it preferable to eat as long as possible. (Since eating Erev Yom Kippur is also a Biblical mitzva)?
A. Most Poskim recommend to stop the Seudas Hamafsekes (last meal) with enough time to reach the shul and do all the necessary preparations for that so important and crucial day.
Horav Shlomo Miller’s Shlit’a opinion is that one should stop eating (at least) a half an hour before the Shekiah (sunset).
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit’a