I posted this Q before and I haven't got an answer.
I was wondering if there is a requirement that a permanent resident has to be in the USA 90 days prior to applying for citizenship! lets says someone is eligible to apply on Dec1st, but was overseas half of november, when this person can apply???

Any answer is greatly appreciated
heartbeat

It sounds like you may be referring to the 90 day requirement for time in district or state. That requirement means that you must maintain your home in the same USCIS district or state for 90 days immediately before applying. For example, if you would otherwise be eligible on December 1, except that on November 15 you moved from Florida to New York, then you'll have to wait until you have accumulated 90 days in New York to apply. But it doesn't mean you can't temporarily visit somewhere else, even somewhere out of the country.

There's nothing to prevent you from applying the day after returning from a brief international trip, if you meet all of the requirements listed in the M-476.