@bernardgreen link states "You can choose not to upgrade to a smart meter. However, you may not have the same functionality as you have now, and you may also be limited with the choice of tariffs." and this it the problem, either you loose split tariff or you have a smart meter.
I had to bite the bullet and have a smart meter earlier this year to get paid for export and have a split tariff, I actually have 8 hours not 7 at the low rate, the smart meter required more room, and items fitted onto the meter board had to be removed, they are fitted where hard to read, so having a in house display (IHD) was an advantage, as was the app, however the IHD will not scroll back to show yesterday, and the app has not updated since 26 Feb 2024 so rather poor, however the tariff does show, standing charge went down a little, and the day rate went up a little, but the night rate is far cheaper, so all in all massive gain having the smart meter.
I know we where I work have at least three independent supplies for the same building, it was start up units, and now we have them all, it worked out it will take 15 years to recoup the cost of removing a supply by not paying standing charge, so they have been left in. But if not using the night rate then no real need for the garage meter to be changed.
This
is the two tariffs I have had, the gain is I can charge up batteries at 8.95p per KWh and then use it until the sun is strong enough to cope with demand. The roof is SW so don't get full output until around 11 am, but before I had solar panel and battery there would have been no gain having split tariff. Up to date the battery has never reached midnight before being fully discharged, but the power used 7 pm to midnight is not that much.