I’m not sure I can add much to what’s already been said.

A word of caution, though: you say that “the more expensive on peak is not a major concern as I don’t run any high energy appliances during on peak ...”. You should do your sums very carefully, although not having a smart meter able to tell you precisely how much energy you use every half-hour doesn’t make this easy. You may be surprised how much electricity is used by what you seem to regard as ‘low-energy appliances’ - televisions, fridges and freezers, for example, particularly older ones, not to mention cookers and electric kettles.

I had a look at OVO’s E10 tariffs for Northern Scotland to see how they compare. In fact, the Simpler Energy plan is far more generous than I expected, with a day rate of 22.88p, night 18.04p and standing charge 59.25p against the single rate of 21.80p with a standing charge of 58.18. Ignoring the difference in standing charge (it’s only £4 a year), you would be better off on the day/night plan if you used more than 22% of your electricity during offpeak hours. The rates will be different in the Scottish Power region.

This is of course academic if your meter doesn’t allow for E10 timings. You haven’t told us anything about your meter or how it handles E7; a photo of the meter itself with its markings and readings clearly visible, and perhaps another of the whole meter backboard with its ancillary equipment and cabling would be very helpful.

There are ways of getting round the smart meter communication hurdles in many parts of Scotland, but they can’t really be used until the smart meter is actually in place. We might have other suggestions once we see your current meter arrangement.