Justice Hoch is exactly right.
Plaintiff filed a complaint that -- stupidly, in my view -- alleged a variety of things, including but limited to some activity (e.g., filing a restraining order, alleged defamation, etc.) that would properly give rise to an anti-SLAPP motion. Defendant was about to file precisely such a motion. But less than ninety minutes before defendant did so, Plaintiff filed an amended complaint. That (smartly) removed the allegations that would lead to an anti-SLAPP motion, but kept the remainder.
Ninety minutes later Defendant filed its motion anyway. It got heard by the trial court on the merits, and the losing party filed an appeal.
The Court of Appeal holds that the filing of the amended complaint mooted the anti-SLAPP motion that was filed in response to the original complaint. That's right. It does. Moreover, the Court of Appeal correctly elects to reach this issue notwithstanding the fact it wasn't argued below. It's a pure issue of law. It's an easy way to resolve the appeal. It's efficient. It's equitable. It's right.
This is why you don't bluster and posture in advance about how you're "going" to file an anti-SLAPP motion. You just file it. Because your bluster may alert them to the need to amend their complaint. And if they do, there goes your anti-SLAPP motion -- alongside its ancillary strategic advantages (plus attorney's fees) -- out the window.
Don't talk. File.