I assume this is the reason they're characterising this as "PHP License V4 will have identical wording to BSD-3" rather than "We will switch license to BSD-3".

I assume this is the reason they're characterising this as "PHP License V4 will have identical wording to BSD-3" rather than "We will switch license to BSD-3". It amounts to the same thing, but the former framing means they're covered by the "or later".