I don't think they would eliminate reporting of field service as we know it (which we all, including them, know is pretty worthless) unless there was a real reason to do so, such as some sort of legal issue. (Wait -- they have many legal issues....) If they have to eliminate it as we know it, I'm sure they'll spin something in its place to keep everyone in line.
Having everyone report online should be pretty easy to launch for them at this point. It might be useful to change the reporting parameters as well, that could cover the shrinking numbers without being too obvious and appear to be an adjustment that accommodates the cart work. (I personally don't trust their numbers, it could be the bOrg is much smaller now than we all know.) It also might make the consolidation of congregations easier, and they might think fading in that situation would be a little harder for people to do.
On the other hand - those of us who have moved around in the last few years might be harder to trace, and can disappear entirely, not a bad thing.
Sadly, I know more than one pioneer sister who would lose their only real status in the congregation if that title was eliminated.
I know if this happens they'll spin this as an urgent adjustment for the time of the end. (Bahhh!) There is so little real change in the bOrg that any change is exciting to the R&F.