I wanna be a double agent

How many different mission strings can I do on one pilot file in Override? I've searched the forums and found a lot of contradictionary info.
I understand that you can do more than one strand if you receive but don't complete their intro missions until you get another one.
What about the UE/Voinian strings? Is it possible to tip the war in the Voinians favor? Can I work for both???

help....

You can get the Voinian and UE strings simultaneously.

YayZoRz!111
...

Do I have to start one before the other or does it matter?

You are able to get the Voinian missions as long as you didn't start the Dreadnought string

See this, old topic, for hints on how to do two strands.