First you must determine if you have basis to deduct the suspended losses. you also should determine if you have any basis remaining for which you can take a capital loss. (technically the partnership has until 9/15/2021 to issue the 2020 k-1 which is the date the IRS would prefer you wait to file). if you file now, then since your return can't be accurate because it is missing the current year k-1 include Form 8082, Notice of Inconsistent Treatment or Administrative Adjustment Request (AAR). it's used to identify estimated K-1 items on your return. that would include the deduction for the passive loss because you don't have a 2020 k-1 to tell you what happened. Also, use the form to notify the IRS that you did not receive Schedule K-1. I don't think Turbotax includes the form which means you'll have to fill out a copy and mail in your return.
if you get the k-1 you'll have to amend.
https://www.irs.gov/pub/irs-pdf/f8082.pdf
