as noted in this post
https://community.ubnt.com/t5/EdgeRouter/ER-X-80-1q-trunking/m-p/2817677
802.1q trunking failed for me when configuring for the first time on a newly upgraded 2.0.3 box.
I previoulsy was on 1.x.? and upgraded directly to 2.0.3.
Once I downgraded to 1.10.9 the link came up immediatly.
