Shifting from Multi-member LLC to Single-Member LLC

I am shifting from a partnership (Multi-Member LLC) to a Single-Member LLC. I know I need to file form 8832 to change the filing status. However, I have some concerns over the timing. 

 

The change was made effective 01/01/2021, but I did not send the form yet. I have just filled it out and am getting ready to mail it.

 

Will it be processed in time to not cause trouble with my 2021 tax return since they're expecting a form 1065 by March 15th?

Do I just mail it certified and file with my personal taxes and not worry about it, or do I need to do something extra to notify of the change?