I have also seen this behavior, in 15.40. e.g. if the miner in question is loading a chest, the chest itself, full or not, is also marked for deconstruction. Overlaying a different type of chest will clear the deconstruction.
This is intentional, construction robots will move the ore to an available storage chest or requester chest and the ore in storage will be prioritized over ore in passive provider chests. You can turn this behavior off in mod settings.
My mining outposts don't normally have construction robots - only logistic robots. I arrived at an outpost with a chest marked for deconstruction and my personal robots retrieved thousands of ore completely filling my inventory. I don't want to disable that feature as it's very useful when the chests are empty. Could another option be added to only mark for deconstruction chests that are empty?