Hi G,
even I was in the same boat like first 1 year visa then again applied took 4 months to get another 457 visa for 4 years, was about to apply for ENS in may as per my first grant visa date, but my MA said have to work for those 4 months again as I was inn bridgging visa that time it won't cover that 457 visa experience.
he said that we can lodge ENS by taking risk , but now a days Migration got bit strict so I said not a problem for me to work for 4 more months, which would be covering all 2 years of work on 457 visa.
anyway I'm going on holidays for 35 days. I have not taken any holidays or annual leaves in the last 2 years.