Retirement tax questions

OK thank you, good to know on the 2019 penalty. I assumed I had until I filed to avoid the second penalty. 

 

Would it be possible to apply the 2018 excess contribution in the 2019 filing? I have not filed 2019 yet. And my current SEP-IRA contribution is well below the max for 2019, plenty enough to allow for the excess from 2018. 

 

How do I go about applying the excess in either case (2019 or 2020 filing)? 

 

Thank you!