Biden is still the president and he’s not enforcing the law. It’s not clear to me that the president can’t grant an extension later once all the statutory requirements are met. What’s the difference between one day and say 10 days?

Putting that aside, the legal theory here—where an exception is there for this purpose and we’re quibbling about its application—is nowhere close to “flimsy” when it comes to constraints on executive prosecutorial discretion.