Stop dropping April Fools' jokes a day early. Now.

There's only one way to do an April Fools' prank properly: Do it on April 1. It's not funny on other days.

Brands love April Fools' day. It gives them some brand-focused exposure and paints even the most corporate-y corporation as a laid back place that's all about fun.

However, this year April 1 falls on a Saturday. And that's just not good enough for some companies, who know those April Fools' stories won't see the same traffic as they would on a workday.

So they've done the logical thing: They've launched their April Fools jokes a few days earlier.

Only it's not the logical thing. It's dumb, it's wrong, and it's even a little dangerous.

The only thing that keeps the April Fools' madness in check is the date: April 1.

Here's how it's supposed to go down: You see an odd news item, but then you remember to check the date. Phew, it's April Fools day. You almost fell for the prank.

But what if it's March 31? Or March 30? How can you know?

Because, sure enough, some companies, like Lexus, Lyft and Burger King, launched their April Fools pranks a full two days earlier this year. And yes, for some stories it's fairly obvious that they're pranks, like Lexus' Lane Valet technology (below).

But take Lyft's elaborate prank, for instance: It's an actual product that actually works, only it's not something that the company ever intends to sell en masse. Plus, the launch was on March 30. Is it an April Fools' joke or not? With pranks like these, it's getting harder and harder to be sure.

Don't get me wrong: I love April Fools' pranks. Companies such as Google and their elaborate pranks made the date fun to cover, especially if you're covering technology, and I wrote about many cool pranks over the years. But I refuse to write up April Fools' pranks if the date's not April 1 in at least some part of the world.

We've seen similar trends in other hot dates that brands love, and that are being dragged into longer and longer periods of time: Black Friday, for instance, has been turned (primarily by Amazon) into Black Friday month. And Christmas as well as Thanksgiving are suffering the same fate. It's not unimaginable that some day in the future, we'll have an April Fools' week or month. Think that's a stretch? Burger King launched its prank a full three days earlier this year.

But it's a horrible idea. April Fools is about making jokes that are quite close to reality, and once you start stretching the borders of that, you're not a funny liar anymore, you're just a regular one.