Jumping progress bar or running process indicator?

I'm developing a process with a predefined number of steps to complete so while process is running I can know how far the process has gotten and how much is there still to be done.

My process executes somehow in a tree mode where each branch has the same number of nodes, but not all branches lead to a result. which means that process will be stepping back to a node that has a junction and try other branch.

This means that if my branch length is 100 nodes it may happen that while process gets to node 75 it sees a dead end and revert back to node 50 and continues with a branch from that junction.

Question

Since my process can define the point of its execution I would still rather display progress bar instead just a running indicator or indefinite progress bar that provides absolutely no feedback to the user.

Is a jumping back progress bar wrong and should not be used at all?

Additional data

Each progress step is a day of the whole range. There's a complex calculation being done for each day but the process work so that:

  1. it takes next day (first one in first step)
  2. makes the calculation

    1. when calculation succeedes it marks all junction points.
    2. when calculation fails go back as many days until it finds first junction point and continue from that point on.
  3. go to step 1 until no more days.

From this process you can see that I can only determine the number of days to make the calculation but not the number of junctions because they heavily depend on each day as well as the path taken from previous steps.

That's the reason why I decided to increment progress bar in terms of calculating day X of Y. and when going back to junctions means I can go back a few days before I can start new calculations... Hence a jumping back progress bar.

Possible solution

I could show an indeterminate progress bar (which is probably better than a rotating gauge) with quantitative information of which day (of all) is being currently calculated and how many have been backed up totally until now.

Would this make sense to users? Should I display other numbers?

I suppose that something else beside the indeterminate progress bar is needed, because this kind progress bar is the same as static content. It doesn't change. So it provides no actual feedback to the user that something is going on...