Why does that matter? SpaceX is setting themselves up for failure by insisting that they need to nail re-entry first. Whenever they focused on a test flight for re-entry I'm wondering why they aren't working on more important things like the payload doors or orbital brimming. They will get the re-entry tests for free!

And even if they don't. The upper stage is cheap enough that it can be expended and still be cheaper per flight than Falcon Heavy. So that tells me that the delays are on purpose. Their test flight planning is designed to maximize ego stroking.