We are about to submit our never-ending manuscript. Since the review process will take at least three months (more likely 6-9 months), we will have no way to pay for the publication after our NSF grant expires. Luckily, there are some good, free journals (no publication cost) we can use for this paper. However, they still charge $3,000 for OA (Open Access). Maybe the funding agent can relax its rules about the expiration date for publication cost...
Honestly, I don't feel terrible about not being able to support OA, since only 7% of my colleagues go for OA.