For iOS, TestFlight beta review is only necessary when you updated the version number. For macOS, I find the beta review to be necessary every time the build version updates. Is this expected?

I'm working on hardware that communicates wireless and wired with mobile systems. Anything non-i[Pad]OS we can connect via USB and achieve great bandwidth, in situations where this is necessary. Since i[pad]OS does not support FTDI class compliant devices through USB (and also omits the IOUSB framework), I wonder whether we have a way to "work around" this, e.g. how about (ab)using another protocol that i[pad]OS allows? Concretely, would you think it's possible to tunnel our serial data stream via USBHID?