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These target dates, deadlines, and submission windows are published in specific program descriptions, program announcements and solicitations that can be found using the Program and Due Dates page or the NSF Website. Unless otherwise specified in a program solicitation, proposals with a deadline date must be received by 5 p.m. at submitter's local time.
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A list of suggested reviewers (along with their contact information) is optional but important and helpful, especially for multidisciplinary proposals. Consider including a list of eight or more eligible suggested reviewers. Be sure that none of them have conflicts of interest with your proposal (e.g., spouse or relative, collaborators and co-editors, thesis advisor, institutional conflicts). Think about including newer faculty members and experienced post-doctoral scholars who have a deep and current understanding of the topic; Program Directors probably know the “household names” in the field, but may not be aware of those individuals. And don’t put this task off to the end of proposal preparation when you may be pushing to meet the submission deadline. Think of suggesting reviewers as part of the process of preparing the best proposal you can. If you take advantage of this opportunity to help yourself you will also assist NSF Program Directors in their role of providing the highest quality merit review of your proposal.
References
NSF Proposal and Award Policies and Procedures Guide Policy Office