So I don’t have an answer for this but this is the same issue I had last year when the AirPods Pro with USB-C came out.
I would say count on Taiwan being 2-3 months behind when it comes to Apple products that aren’t the iPhone.
I believe it’s because the Taiwanese government has additional scrutiny and approvals for any WiFi/Bluetooth device and each new product has to go through this process to become available.
The workaround is importing them. If you see them on third party e-commerce websites, they can sell them because you’re importing under “personal use”. The additional scrutiny comes from reselling the product.
Also FYI you aren’t able to import too many WiFi items without a broadcast license. I ran into this with wireless webcams. Because I bought 3, I needed to provide the license. I ended up getting it returned and asked the company to ship one at a time box by box and it was fine.
tl;dr:
Everything Apple takes longer in Taiwan except for the iPhone. Expect 2-3 months delay.