I'd like to get a better understanding of the difference between these two sentences:
1) He has just come.
2) He came just now.
What I do know is that 'just' means 'recently/now' and 'just now' means 'a short time ago/ a moment ago'. In addition, the present perfect implies that him coming is related to the present one way or another; for example, a further context would be ' The manager is angry because he is late.' The past simple doesn't relate to the present time.
Did I get it right? Am I missing something?
Thanks for your help.