It took 11 months before I got my second key notification. They are working their way up from October of 2022 so there are a lot of second keys to fulfill. It will either show on your Toyota app or they will send you a recall notice in the mail.

Check your app to see if you qualify for the Second Key Delivery program yet. This affects most cars sold and delivered from Nov '22.

I haven’t really heard of others doing this though I’m sure it’s happened, but I was in the same boat as you (waited nearly a year) regarding a Sienna key fob. I ended up calling my local dealer a couple weeks ago and asked their parts department if they had any spare keys for sale. They verified they had 3 in stock, identical to mine. I said I bought a key a year ago with my Sienna and it never showed up and I asked what they could do to help. We scheduled a service for the following week and I got my new key and, oddly enough, a letter from Toyota in the mail that same day saying it was time to schedule an appointment to get my second key fob. Crazy coincidence, right? /s

Might be worth a shot.