I have previously never really cared about Tag Team Arena at all, usually sitting in Bronze 1 with 1 man defenses and making the bare minimum per week to get the Ancient shard.  A few weeks ago I thought I would actually make an effort and move up a few brackets to see what it was like

So week 1 I pushed into the green, then the reset happened and I moved to Bronze 2.  Week 2, I pushed up into the green again and then after the reset got put into Bronze 3.  Week 3 I did the usual and got put into Bronze 4.  So far, so good, the system seems to be working.

Then week 4 comes around which has just finished.  I again pushed into the green and finished the week in that section, and after the reset I am now back down in Bronze 3, and I have no idea how?

I didn't finish in the red, nor did I even finish in the yellow.  According to the in game help, being in green means you will be promoted a tier, but with the caveat that there are a certain number of places available in the next tier so if they are full then you simply might not be promoted at all.  It doesn't say you will be demoted though?  

It's slightly frustrating because now it means that I have to wait a week to get back into Bronze 4, and then another week to move to Silver 1, but even that feels like it isn't guaranteed now.  I could be sitting in the green and just thrown back to the previous tier, which makes me wonder what the whole point of this content is

Probably yet another reason why no-one plays tag team arena