Yeah good idea, fingers crossed us 2019 guinea pigs aren't screwed over too badly xd
I guess it'll be important to remember that, at the end of the day, it's going to be the same pool of (hopeful) students sitting the exam (whether it be UMAT or UCAT), so that part won't change. And the part that has changed has changed for everyone. So no-one can really be "screwed over". It's not like the number of places available will change, so whether the spread is greater or not, it'll still be the same X number of top performing people who secure offers. If that makes sense.
If the individual universities (in Aus or NZ) decide to change how much weight to allocate to UCAT/interview/written application/PQA/other factor, then they'll (presumably!) be doing that for ALL students applying to their course. I know the uncertainty makes it more nerve-wracking, that's completely understandable, but it's counterproductive to start worrying about being screwed over because literally everyone is in the same boat so I'd think it would be hard to justify that that could be the case.