I found conflicting information about the subject: BBC World Service states that:
And we cannot use unless with would to talk about unreal future situations:
If he didn't take everything so seriously, he would be much easier to work with.
If he weren't so bad-tempered, I would help him to get the work done.
We cannot use unless with would have to talk about unreal situations in the past either:
If you hadn't driven so recklessly, you wouldn't have had this accident.
If you hadn't had that last glass of wine, this would never have happened.
While Education first website shows usage in all conditionals. What is correct then?
Why I cannot find anything about this usage besides that BBC website?