The cause for the apparent timing problems in the gospels conflicts between different calendars. This is reported as a new discovery. But it's not. I've been aware of this, because of news reports, for more than forty years. (That also implies it's been known for significantly longer than that.) The only thing new is this individual's suggestion that Easter should be on a fixed date on our current calendar version.
Sorry, but that strikes me as dumb. The date of Easter ties absolutely to the date of Passover new calendar or old. And that means it should still be on the lunar calendar, and not fixed on our current solar calendar.