"it's high time"+past simple vs. "should have"+past participle [closed]

Question

1. Can we use "it's high time" + past simple interchangeably with "should have" + past participle?

It's high time you revised your lessons VS. you should have revised your lessons

2.Do these sentences have the same meaning?

Answer 1

To answer your two bullet points in one:

Yes, both phrases are correct and mean pretty much the same, except they do not express the same urgency. This you could fix appending “by now” to the latter.

It's high time you revised your lessons

Mariam Webster Dictionary: “It's high time.”: used to say it is time to do something that should have been done a long time ago

^{btw. High time or highest time is very similar to the German expression “Hoechste Zeit”}

you should have revised your lessons by now

Grammarhow: The phrase “by now” is a common way to talk about how things might come to an end at the present time.