Macbook Air 2015 - Is 4k @ 60Hz possible?

Macbook Air 2017 - Is 4k @ 60Hz possible?

Brought my "surplus" home monitor in to work with my MBA, which I thought would work properly at 4k after reading so here:
https://www.macrumors.com/2015/03/25/2015-macbook-air-4k-display-60hz/
and
https://9to5mac.com/2016/06/04/how-to-enable-4k-60hz-resolution-2016-macbook/
(tried both CoreDisplay and IOKit patches AND SwitchResX).

However its stuck at 30Hz which is pretty painful. I know the HD6000 integrated graphics can do 60Hz 4k.

Monitor is a (admittedly basic but functional) 28" 4k "Electriq EIQ-284KMB" display, which has 2x DP inputs (and 2x HDMI).
Im using a mDP to Full DP adapter to the standard Full DP cable.

2017 MBA with MacOS 10.13.1


Is there something else I should be doing? Or a specific cable to try? Thanks!


EDIT: This is actually the 2017 model not a 2015, I was fooled by the fact its basically 2015 tech despite being "new".

Here's Apple support article on support for 4K displays:

Using 4K displays, 5K displays, and Ultra HD TVs with your Mac

Interestingly, they state 4K displays @ 60Hz are supported for a variety of models like "MacBook Pro 2015 and later", but for the MacBook Air, only the 2015 model is listed. I'd have to wager that you are out of luck on this. Crazy, I know.