Comment by 542354234235

>If they didn't need maintenance why upgrade them?

We don't know, but there are other reasons besides maintenance and it is a huge unfounded assumption to say that is the only reason. Upgrading an existing installation for better performance is likely orders of magnatude less expensive than building additional units, building the archor points, and emplacing them, so it could have been getting more data out of less budget.

They may not have permits/authorization for additional locations yet.

The upgrades may provide a significant ROI improvement and the only reason they didn't upgrade all of them was to leave one to look at long term reliability while sacrificing the improved ROI.

But fundamentally, we just don't know. While required maintenance is one possibility, it is by no means the only one.