That definitely looks that the ECV will need to be relocated to the new enclosure. (To me it also looks possibly just a bit more than 1-metre overall, assuming that your existing box is about 500mm wide - mine is 485mm).
If you want it done without the gas being off for too long then the way that I would timetable it is:
- Let OVO replace your current meter where it is now. You say that’s already booked.
- Get a new wall mounted backplate and enclosure fitted where you want it to be.
Then when you are ready, and preferably all on the same day because you will have no gas until it’s all done: - Get the ECV moved to inside the new enclosure, by the transporter.
(They can probably leave once they have done that and checked that it’s gas tight). - *Have your house gas piping extended to the new enclosure, by you own qualified gas fitter.
- Get the meter moved to inside the new enclosure, by OVO and connected to the new ECV and piping.
- Have all new connections checked for gas tightness.
*If that yellow pipe is the gas pipe into you house, or if the pipe to inside is behind the box, then it will definitely need to be extended to the new meter enclosure.
I doubt that either the meter, or transporters, engineers will to do that for you, that’s your piping not OVO’s or the transporters.
Your gas fitter may be able to put the extension pipe in place from the new box to the existing pipe and leave the final connection to the existing pipe until the gas is off on the day of the meter move.
So you would end up with 3 different gas engineers/fitters, each having to do their own bits of the job in a particular order.
(and keep your fingers crossed that it all goes smoothly).