the IRS has stated they may provide relief for failure to file form K-3 for 2021. not specific so I'm assuming the IRS won't assess any penalties for failure to file or disallow credits or deductions
if you don't want to risk it, your only option is to extend. I got notified by a partnership that' is not likely they'll have their K-3 to me before 10/15/2021 which means for me either filing late, filing and amending. or just file without it and see what the iRS does.
there is a 5 letter word that comes to mind.
