When filing via a facsimile, the filing date will be based on the:
time of receipt at Office
e.g. if filed at 10 Pm in LA, it’s 1 am ET and you will get filing date of next day.
When filing via a EFS, the filing date will be based on the:
time of receipt at Office
Same as a fax
To be granted a filing date the same as the mailing date, you must:
Transmit a Rule 1.53(b) or (d) application to the Patent Office by Post Office Express Mail before Midnight of the mailing date