Tender on M25

This morning at 08:00 I passed a tender in British Railways green livery on a low loader, parked up under the M25 at Junction 17, Marple Cross (between the M40 and the M1). Does anyone know which locomotive this belongs too and where it was going to (and from)?

 

Could be 30777's tender going back to the GCR from the Bluebell.

 

I passed 34028 Eddystone on the back of a low-loader on the M1 on Tuesday 9th heading north, could it be for this?

 

Could well of been 71000s off to the CVR gala......its now connected back to 71000 and is on shed at the CVR

 

Deleted.

 

Could it have been 70013s tender, from memory it was left at Southall, loco currently in Crewe, Cab and fittings at GCR ?