Pump basal setting for long period at night

For several months now I've had to adjust my basal settings with zero insulin for several hours while sleeping. here are my basal settings now.

12am 0.0u, 3am 0.75u, 10am 1.4u, 2.30pm 1.75u, 5pm 0.5u, 6pm 5.0u, 7pm. 2.0u, 8pm. 0.0u.

I'm keen to know if anyone else has zero settings like this. My DSN does not help me with information about this situation and my management is all done by myself using Libre/Miaomiao/xDrip. I assume I have a big dump of glucose from my liver at 6pm causing a complete lack of glucose from the liver for 7hrs from 8pm. I also appear now to be producing a small amount of my own Insulin. I'm 81 yr old and maturity onset T1. BG is slowly getting harder to control. M last hba1c was 6.6. Any thoughts on this would be greatly appreciated.

Thanks Response for your reply. I sometimes have a wine before evening food. I'll keep an eye on it.

Thanks for your input Chas C. Like you, I think it must be very unusual to need such a large insulin dose and then zero insulin for several hours. It seems to me the main problem must have something to do with the liver. This started about a year ago with a 2hr zero segment needed from 11pm to 1am and has progressed to the big glucose dump and extended zero time. I'm still managing to keep control but I'd be ******** without the monitor. I would really like to have someone respond who has the same thing happening to them but I think the chances are slim. Have you ever needed a zero insulin segment? That alone seems very odd to me. Thank you very much for your response.