Question about the premium chest, am I suppose to get two, or one?

So after googling for a while and reading it seems that Riot had made it so the free 400 RP you get with a new account is instead replaced by a premium chest that contains both ashe and garen. Yet, after further searching I found out that at level 5 you also get a different premium chest which it contains "a skin, a ward skin and a champion " while it is supposedly guaranteed to give a skin to any random champion that you own. So as to that, I'm saving up my ip to open up a skin for that champion, and so the question comes to mind- was the level 5 chest I got the one with ashe and garen, or was it the latter? And if the latter, what happened to the chest with ashe and garen? I can't find any sources on riot changing its policies, but I did find sources on different people obtaining two premium chests: http://boards.eune.leagueoflegends.com/en/c/bug-reports-eu/NwQvb3NT-peopole-who-get-2-premium-chest-and-2-free-keys http://boards.euw.leagueoflegends.com/en/c/bug-reports-eu/m2HEnMzx-i-got-2-hextech-premium-chests?sort_type=best https://www.reddit.com/r/leagueoflegends/comments/4c54uc/i_got_two_premium_chests/ https://www.youtube.com/watch?v=_RazI2W9SYw (my speculations on the chest are confirmed on this video)

And so if I was supposed to get two chests why did I only get one? My answer to that would be that it was a bug with me using the new client starting off, and if so, how do I report that bug? Finally, how do I obtain the second chest if I actually was supposed to get it.