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For the Severn Valley at least they used to do a lineside permit scheme. This has now been stopped however anyone who still had an in-date permit can use it lineside until it expires.
If you remove the chip you would need to replace it with blanking plate.
As posted by @4COR from what I have read a model brand new out of the box should run on DC with DCC chip installed.
Realtimetrains.co.uk only shows what the train is timed for not necessarily what will run it. A number of services now are timed for 80x but run with Pendolinos.