Quota arrangement for "Mode of transport" or "means of Transport " - Need 70% truck and 30% rail

Simple Supply chain network :

One Product , Product A , one Tlane between Plant and DC with Truck and Rail as Means of transport .

Requirement :

If there are deployment orders totaling 100 qty ( From Plan to DC ) , I want 70 to be sent by Truck and 30 to be sent by Rail .

I have experimented with giving costs to modes of transport , eventhough both means of transport are considered I want a specific ratio .

any creative way by deploying twice or by updating tlane using mass update or even if it involves development , we are ok . I have identified some badi's in deployment but no success

Thanks for any pointers