Hey @nopro404 thanks for this.
I followed your script to a T, but doesn’t work for me.

Ive only got one WAN, which is my phone, tethered.
Using it is rinsing data really fast, so want to limit my connection to it.
On my device, in Interfaces, my Tether is ETH1

BASIC SETTINGS > eth1 and limited UL/DL by 50%
QUE DISCIPLINE > cake+piece of cake
LINK LAYER > I’ve tried all three DEFAULT, ADSL & ETH

Ive also done all BASIC SETTING using LAN aswell as ETH1

Everytime my bandwdith UL/DL doesn’t change.

I read that SQM is for specific devices, not for general throughout.
But if that’s the case, then where do I nominate/designate the device?
Or is it QOS that is device specific?

Im stumped on this.
i paid someone techy who knows Open WRT and they said its a firmware glitch.
Im running 18.06 on GLI 3.105.
All the helps files (yours included) say it should work fine.

Really confused.
Any help or nudges from anyone greatly appreciated.

Thanks
D