Who owns the roads involved, if they are NR» owned but have public right of way then NR can authorise what the contractors can do, if they are local authority owned then a licence is required
I'm not sure who owns the road in question but thought that as they were used to access other businesses they weren't owned by NR (but could be wrong) .
I seem to recall many years ago that the "exit only" flow which leads out of the station was reverted to two way operation and during this time the no entry signs were covered up.
There are some local drivers who do drop offs In the morning who drive into the station via the "no-entry" entrance to save using the proper route.