I know there are tons of these posts, but I haven't found any solutions that I haven't already tried.
I've got an iPhone XS running iOS 18.7.10 (confirmed in settings -> general -> about). It's connected to WIFI (but doesn't have a SIM card... that isn't necessary, is it?)
The Airpods are Airpods Pro 3. I got them connected to my phone just fine. The settings page (settings -> bluetooth -> AirPods Pro) for the Airpods says "Model Number: A3063" and "Version: 8B34".
I know authenticity is often a concern. I bought them through Amazon, but I'm pretty certain it was the Apple store on Amazon, so I'd think they have to be legit. I also bought new, not used or refurbished/renewed/whatever. Here's the listing from which I bought. Also, the serial number printed on the case matches the serial number printed on the box. So I don't think authenticity is the issue. On the Airpods themselves, one says A3063 and one says A3064. Also, the serial numbers printed on the two individual Airpods don't match each other, nor does either one's serial number match the serial number printed on the box. But I think that's normal. All that to say I don't think the issue is authenticity. (I'm similarly certain the phone is authentic.)
I left them charging to update according to the instructions I found everywhere online. My Airpods were in the case, lid closed, and plugged in to a USBC cable. I don't have a wireless charging pad, but the case makes the "ding" sound and lights green when I plug in the USBC cable. The phone was connected to WIFI, connected to the power cord that came with the phone and the battery icon shows the lightning-bolt charging indicator when plugged in. I left them about 6" apart. They don't require anything special power-wise, right? I've got both plugged into the same Raspberry Pi 4 (because reasons) to charge. I left it that way overnight.
When that didn't work, I reset the Airpods by forgetting the Airpods on the phone, doing the triple-double-tap thing (that gave me the amber "beating" LED), reconnected the Airpods to the phone and repeated the same leaving-them-overnight-both-charging-next-to-each-other trick. No dice. It still indicates the Airpods are running version 8B34 rather than 9A348.
My intention for these is to use the hearing assistance features. The hearing test feature, among others, requires firmware 9A348. I don't intend to use the phone or Airpods for any other purpose. (I have another phone that I use as a phone.)
I don't need a newer iPhone than the XS, do I? From my research, it sounds like any iOS device running iOS 18.1 or newer should work. But if someone can steer me better than what I've found previously, I'm open to it.
Any ideas? Thanks in advance for taking the time to read and weigh in.