hard to tell. i dont believe there is one best way to do it. at some production u need a FULLY loaded bluebelt. and at some u just need like 1 iron plate per minute... if u get the point.

so i recommend to find the best way suitable for your gameplay. there are alot of options u have. in the end i dont recommand splitting at all when u use a belt. in the end u want a EXTRA belt for every production... just to keep things running at the end.

because everytime u split, the belt gets more and more emtpy. and in the end u get nothing for a long time... so my friend. all the best with your base. let me know how it goes