I filed an extension for our 2018 tax return. I did this because a K-1 document isn't going to be ready by 4/17/18. Is there a way to amend an extension?

[dailyraces]

Yes, for this year's filing deadline. The mentioned (delayed) K-1 was forecasted to show a loss - the accountant has just informed the shareholders that the K-1 will actually show a profit. I will have taxes owed on this income. When I filed the extension - I had answered zero taxes owed. Hence my question about amending an extension.

[evanbrown620]

I'm a little confused. Do you mean it isn't going to be ready by this year's filing deadline 4/15/19 (4/17 if you are in certain states and DC).  There is no need to amend an extension. File the appropriate return with all schedules by the extension deadline, which is October 16, 2019.