I am live streaming remotely with a peplink b one 5g router, I am combining WIFI two cellular sims and a nighthawk m7 cellular, to try and achieve a stable upload to support 1080p 25fps stream to YouTube at a stable bitrate of 8mb. At home I have two fibre optic connections combined I have upload capacity of 1gb, but when I try to test my setup and combine these via the speed fusion tunnel to the SFC london cloud, I only manage to achieve 4mb upload speed on the speed fusion tunnel. I have tried multiple configurations and outbound rules and static IP for the Magewell Encoder AIO, but I am unable to achieve anything more then 4mb upload. I am new to this tech but I have tried many tutorials and webinars and setup in the web admin many different ways with no success. Can anyone give me an idiots guide on the best setup to achieve the strongest upload speed please ? If I can get my setup correct at home with the correct configuration then when I move to remote location I know my setup is at least correct please help me 
Some methods of bonding will limit you to the speed of your slowest connection, try taking each cellular connection out one at a time and see if it improves.
I will give that a try but be good to understand if I have the configuration right in the first place and keep getting conflicting what is the best setup, is there clear set-up guidance as I am not 100% I am even setting it up right, I combined two connections both along were over 150mb upload but I still only get 4mb on the tunnel ?