Investors & landlords

No, Form 3115 must be filed with your timely filed, original tax return.  In other words, it needs to be filed WITH you 2016 tax return.

Sort of.  Form 3115 will 'catch up' on the missed depreciation by adding it to your 2016 tax return.  So it will effectively give you a larger 2016 refund (or less owed).