The Too Late ones were ruled to be so because whatever had happened had happened and so it was too late to change anything. All the votes had been cast.

The legal term for this is "laches". It's an ancient rule that says you can't wait an unreasonable amount of time to sue over something, if that delay causes problems for other people. If you have a problem with election procedures, you're supposed to sue before the election so that they can be fixed in time for the election. If something happens during the election that you couldn't have anticipated, then you are allowed to sue after the election, as long as you're reasonably prompt about it.

The Too Early ruling was because nothing had actually happened that could be prosecuted yet. It would have been a case based on speculation rather than fact.

Again, this is a longstanding legal principle. You can sue over something that is clearly about to happen, but you can't sue to prevent something just based on a guess that it might happen. Can you imagine the chaos if people could sue each other over hypotheticals?

There is no dispute that would have been "too early" before the election and "too late" after the election. Many disputes over election procedures were heard on the merits before the election. Some disputes over fraud were heard on the merits after the election.