I have a single entry tourist visa which gives me 60 days, i am here for 90 days - question is do i go to immigration in the first few weeks for the 30 day extension or should i leave it till the last few days before my 60 days runs out? Thank you

You can go to immirgation in the last few weeks of your current 60 days and get the 30 day extension. The extension starts when the 60 day ends, so you don't lose any time.

You can do it a couple of weeks before your 60 days end. Some office will do it 30 days early.

Great thank you for your help