I have tried this with my second account but I am unable to unlock the clouds over the stone resource bases despite my radar being level 9 - according to wiki, it should be unlocked at radar 6.
The in game help offers this explanation:
Note: if you have many unlocked clouds and decide to upgrade your Radar even further, not all clouds at that level will become available. You must then unlock other available clouds for the newer ones to appear.
Clearly, I do not want to open the available clouds as that is the whole point.
Do I need to keep upgrading my radar further to unlock these clouds?