43 CFR §1822.17

1. (a)BLM considers two or more documents simultaneously filed when:
   1. (1)They are received at the appropriate BLM office on the same day and time; or
   2. (2)They are filed in conjunction with an order that specifies that documents received by the appropriate office during a specified period of time will be considered as simultaneously filed.
2. (b)An application or document that arrives at the BLM office where it is to be filed when the office is closed for the entire day will be considered as filed on the day and hour the office next officially opens.
3. (c)Nothing in this provision will deny any preference right granted by applicable law or regulation or validate a document which is invalid under applicable law or regulation.