Level 15

@joshuabarksatlcs  Yes, 1998!  Back when the Journal of Accountancy and Motorcycle Maintenance didn't provide links to the "procedures, terms and conditions" referenced in their articles.  Had they done so, it would have been to Temporary Regulations here:

Of course, some Temporary Regulations remain that way for decades.  Somewhere, though, these may have been made permanent, maybe with changes.  The way I read them, they say:

For any Form 3115 filed on or after
May 15, 1997, application for
permission to change the method of
accounting employed shall be made on
Form 3115 and filed with the
Commissioner during the taxable year in
which the taxpayer desires to make the
change in method of accounting.

So that doesn't even allow 180 days after the close of the year.  Or does it?