apply mask animation to multiple masks

Hi, I'm noew to After Effects.  I have multiple dust spots on some clips and have been using masks with content-aware fill to fix these.  Its been working great but on one clip somehow all the dust spots move in tandem partway thorugh the footage.  I know how to animate a single mask to folow a dust spots as it moves (Ive been doing this manually by adding keyframes as the video image behind the dust spots is too disriptive to use mask tracking). My question is, since they are all moving together, how can I apply the animation of one mask to other so they move in the same way realtive to each inital starting point?  I thought maybe "copy with relative properties link" migh be it -- but that didnt work. There are dozens of these masks --one for each tiny dust spot... so it would be helpful if I could apply this movement pattern to all at once. 

Thanks for any suggestions!