Rule 12b-25 also provides that if the report could not have been filed by its due date without unreasonable effort or expense, then it may still be deemed to have been timely filed if the company:
timely files its Notification of Late filing; and files the late report within the applicable grace period (no later than 5 calendar days in the case of a quarterly report, and no later than 15 calendar days in the case of an annual report, regardless of the company’s filer status).
I think the interpretation of the rule hangs on how interpret the word "then" . Read it one way and it says the company must file within 1 business day in order to avoid being late. The other read says that "then" the company MUST file a late filing request. That one word makes a lot of differance to the meaning.