This response is based on the information provided. We suggest you discuss with your contracting team, program manager and/or legal department as appropriate.
Excerpted from the SF 1442
"10. THE GOVERNMENT REQUIRES PERFORMANCE OF THE WORK DESCRIBED IN THESE DOCUMENTS (Title, identifying number, date)"
In this block the Air Force identifies what it wants done, e.g., the Performance Work Statement, Statement of Work, and/or specifications. We suppose it is not incorrect to put a proposal validity date in this block, but it does not belong here; this block is for contract performance information, not solicitation information.
"13. ADDITIONAL SOLICITATION REQUIREMENTS:
d. Offers providing less than ________ calendar days for Government acceptance after the date offers are due will not be considered and will be rejected."
This block is for solicitation information and the proposal validity time belongs here.
While we do not speak for the GAO or the courts, we believe were this to go to protest, the ruling would be the block 13 "120 days" would be held valid, not the block 10 August 5, 2020.
If your office intends to continue identifying the proposal validity time in more than one place, be consistent and aware that the binding date is what is in block 13(d).