Hello,
I've noticed a rather annoying bug: Construction Drones don't return old tiles when they place new ones when they place a ghost on exisiting tile, i.e. concrete on stone brick, etc.
I'm really tight on resources (especially coal) in my current playthrough and seeing a whole road for Transport Drones replaces by stone brick after expanding a city block was rather unpleasant :/
Edit: mod and Factorio are up to date as of writing this (Factorio 0.18.31; Construction Drones 0.6.6)
