If I get Kickstarter revenue next month but don't launch until end of year. When is royalty due?

I am getting ready to launch a Kickstarter.
Do I notify Epic now of my game and pay them after Q2 for the Kickstarter revenue (if successful)
Or is that revenue due after the game actually launches to the public?

"Royalties are due on revenue from Kickstarter or other crowdfunding sources when the revenue is actually attributable to your product. For example, if the user is required to purchase a particular funding package to obtain access (now or later) to your product, or if that package gives the buyer benefits within the product such as in-game items or virtual currency.

Here’s an example of what we mean by “attributable”: Assume you provide two tiers of offers, a signed poster for $20, and a signed poster plus game access for $50. No royalties are due on ancillary products like posters, so no royalty is due on the $20 tier. On the $50 tier, the user is paying for the poster with a $20 value, and that implies that the remaining $30 of value is attributable to the product. So, for each $50 tier sale, you’d pay a royalty of $1.50 (5% of $30)."

Source: Frequently Asked Questions - Unreal Engine

Yeah I read that, but I guess I was not entirely clear…

Are you saying that yes I should notify Epic now or no… I should notify Epic when I get closer to the actual release date?

As I read it, if you have tiers in your Kickstarter campaign, that are attributable to your game. Like a copy of the game when you release. Then that is royalty you owe. You say you are getting ready to launch the KS campaign, you probably don’t need to notify Epic until any money is actually in your bank account. You don’t even know if your KS will reach its goal.

Some more information on reporting:

“Royalty payments are due 45 days after the close of each calendar quarter. Along with the payment, you must send a royalty report on a per-product basis. For more information, see here.”

Even if your game is not yet released, if you have KS money in your bank account, that is revenue earned.