Adjust path when destination occupied

I am making RTS game,so I have groups of units and I want them to make from one place to another.

I have set up Pathfinding and RVO, but when I move group of units, they move, then the first unit arrives at destination, is being locked in (this is intended) and then other units just circle around it as it occupies the destination.

I would like them to adjust the path (when the destination is occupied) and choose something like closest unoccupied space or so.

What is the reccomended way of dealing with it?

Also, my game is 2D.

Any tips? What I want is basic RTS functionality from games like Warcraft 3.

Did you ever find a solution to this?

I think you can use beta, there are tools suited for that.