What year is on the K-1---2016 or 2018?

No.  Don't amend your 2016 return yet. 

There are two issues to consider:

1. For what year is the executor filing the estate return?

• If they are filing a 2016 return for the estate, then amend your 2016 return when you get the distribution.
• If they are filing a 2018 return, include the K-1 in your 2018 return (see below).
  

When will the funds be disbursed?

• Contact the executor of the estate and ask when he/she plans to distribute the bond interest.  It should be soon since they filed the estate tax return saying that the distribution has already been made. 
  
• If you receive the distribution before you file your 2018 return, include the K-1.
  
• If you haven't received the distribution by the time you file your 2018 return, do not include the K-1 information in your return.  You can amend your 2018 return when you receive the funds.
  

Thank you for responding.  I have not yet received a distribution but wonder if the interest charged will continue to build until I pay the tax, interest and penalty.