Do we know who owns this land? If the way is (temporarily) no longer a legal PRoW, it's still "permissive" for a given mode of transport if the landowner still allows passage, which the gate and signage situation seems to suggest.

I do agree with you that it's pretty outrageous what the council have done here, it sets a terrible precedent for landowners to "temporaily" close PRoW's they don't like on spurious grounds.