The filing deadline for a partnership was March 16, 2020. That deadline was not postponed.
From the IRS web site:
Q. Are the filing deadlines for partnerships and S-corporations whose returns were due to be filed on March 16, 2020, postponed?
A. Notice 2020-23 does not postpone any return filings that were due on March 16, 2020. If a fiscal year partnership or S-corporation has a return due to be filed on or after April 1, 2020, and before July 15, 2020, that filing requirement has been postponed to July 15, 2020. For information about additional relief that may be available to partnerships in connection with the CARES Act legislation, please see Rev. Proc. 2020-23 (PDF).
Filing and Payment Deadlines Questions and Answers
