My smart meter couldn't be installed because the traditional meter is too old and has asbestos fuses - what should I do now?

That’s what prompted the board replacement:

 
A multi-rate smart meter would replace both the old meter and the clockwork time switch.

I wonder how far out of kilter the meter is after 30 years of service. I bet it’s about as good as new …

@James0701 Are you on a day/night tariff? How much electricity are you using overnight?

Many customers have discovered that they’re paying over the odds on a plan like that, because their offpeak usage is not as high as it used to be. Unless you have an electric vehicle, just about the only reason for having a multi-rate plan is if you normally use night storage heaters to keep the place warm. Even if you do have an EV, there are cheaper ways of charging it at home.  

We did have night storage heaters, from last reading use very little low rate.

The email originally OVO sent me said if the meter wasn’t changed it would be locked on the higher rate from 31st March when whatever makes it change shuts down.

Will follow up on getting a single tariff 

That sounds unlikely. The ‘shut-down on 31 March’ is presumably referring to the Radio Teleswitch (RTS) service, which uses long-wave radio to control the time for peak/offpeak usage. It sounds as if there’s something like an RTS flag on your account, which you should ask Support to have removed.

What you have is an electro-mechanical time switch* which turns the night storage heaters on and off, and also changes which of the two registers in the meter is active. When the heaters are on, the meter will record on the Low register, and the rest of the time on the Normal register. If you’re on an Economy 7 plan, you will have been paying the high rate for most of your electricity, so you should waste no time asking to be moved to the single-rate tariff.
  
  

* I just wasted an entertaining half hour watching this video all about that time switch: Time Switch : How to wire a Horstmann Vmk 7 SRS Rate Changer. (youtube.com)

Thanks once again, I did post a copy of the letter OVO sent me yesterday but for some reason it’s disappeared !

I noticed. The mods may have removed it thinking that there was a bit too much PII, so I obfuscated it all 🙂
Here it is:
  

Its clearly a mistake. Once you get the backboard sorted out, you should be clear to get a shiny new SMETS2 meter, with any luck all in one go.

Once again many thanks will let you know outcome it must also effect the other 39 people who live here!