When the device family is provided without an explicit model number, we
simply choose the first available model. But since new models are being
added all the time, this default model is not guaranteed to remain the
same. That's not desirable because it can alter the behaviour of the
application.
The introduction of the Aeris 500AI is an example of this problem. The
default model in the vtpro family used to be the Oceanic Versa Pro. But
because the Aeris 500AI has a lower model number, it automatically
became the new default model. Since both use a different protocol
variant (MOD vs INTR) they are not interchangable.
The default model is now hardcoded. The best option is of course to
provide the model number explicitly!
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