Who is permitted in the United club?

A) star alliance gold travelers on international tickets B) United club members C) guests of the above D) people who pay the fee for daily access E) people with one time access vouchers

So if i have my travel in the morning 5am in business class i can't go in the night before 9pm for getting something?

Ellery has it right.

Members and their guests or if you pay for a day pass

Those who have a pass (from airline, credit card, ...) or who have 1st/business same-day tickets. Not sure if anyone can buy entry (I think Delta does that).