When i saw Axl last year in Australia, Korn started at like 7:55 and played till 9:10. And then Axl came on at 9:55. Reports said he was two hours late tho....
but you can get lucky with Axl.
Good luck
Had about the same thing. September last year the opening act ended 8:30, GNR allready started 9:20, though the newspapers said he was very late

... I just arrived at 9:15 not expecting the band to start pretty soon jet

, so I had to hurry to my place when suddenly and unexpectedly the dark intro started.
So far in this tour, they mostly started pretty early.