Answering from Germany but my answer should apply worldwide:

I had that issue two times. Each time I just gave my insurance a short call to their service line. I described my plans:

First time, I was too ill to safely drive myself. Problem was I've been to another city. So I asked a friend and his partner (she's also a friend of mine but not as close), if they could fetch me and my car. I called my car insurance. They told me it wasn't covered as a regular occurrence in my policy but they would allow it as an exception, because it was safer (also for them) to do so.

In between I upgraded my policy to include arbitrary drivers but forgot that I had done so.

Second time, I intended to lend my car to my sister-in-law while I was on vacation. They checked my policy and said it's OK and I wouldn't have needed to call to tell them, because I had upgraded my policy.

Calls were less than 10-15 minutes including waiting in the line. Apparently insurance hotlines are not as crowded as phone company hotlines. However that's probably because people are hesitant to call the former for some reason.

The elegance of this answer lies in that your company will know your policy, country specifics and can still make exceptions. Whether you trust a company to uphold exceptions agreed upon at their hotline is another question. I recommend writing down the name of the service employee as well as time and duration of the call.

Answering from Germany but my advice should be applicable worldwide:

I had that issue two times. Each time I just gave my insurance a short call to their service line. I described my plans:

First time, I was too ill to safely drive myself. Problem was I've been to another city. So I asked a friend and his partner (she's also a friend of mine but not as close), if they could fetch me and my car. I called my car insurance. They told me it wasn't covered as a regular occurrence in my policy but they would allow it as an exception, because it was safer (also for them) to do so.

In between I upgraded my policy to include arbitrary drivers but forgot that I had done so.

Second time, I intended to lend my car to my sister-in-law while I was on vacation. They checked my policy and said it's OK and I wouldn't have needed to call to tell them, because I had upgraded my policy.

Calls were less than 10-15 minutes including waiting in the line. Apparently insurance hotlines are not as crowded as phone company hotlines. However that's probably because people are hesitant to call the former for some reason.

The elegance of this answer lies in that your insurance company will know your policy, country specifics and can still make exceptions. Whether you trust a company to uphold exceptions agreed upon at their hotline is another question. I recommend writing down the name of the service employee as well as time and duration of the call.