The North panels will generate most very early on and late on in the day away from the peak generation time though. On a tariff like Flux they would be perfect for 4-7pm export.Unless you are using the power of the north facing panels yourself in summer then north facing panels worth is quite dependent on export rates staying high. The cost difference is quite high here. If export rates during summer peak generation hours fall (a plausible scenario) you will never see a return.

, so I'm going to start looking at maybe getting some quotes, I'm using approx 4300kwh per year and the picture shows my roof orientation, arrow pointing south.