phased boid actions

Ok heres the problem, I have made a cloud of boid particles , with a mesh object (in this case butterflys) assigned to the boids…

I have shapekey driven animation for “flapping” my boid particles now it works as expected, the only problem is, the boids are all “flapping” in sync… is there any way to adjust the phase of each particles individual animations to obtain a more random result. I have tried adding randomness to the particle systems settings , but it seems the particles animation remain synced…

the only alternative method I can think to do this, would be making several versions of the butterfly with slightly offset animation sequences… this seems like a bad way to do it. as it would not obtain the satisfactory result without having a LOT of versions, each with their own particle system… making it slow and making it difficult to change the flapping cycle later on…

Am I overlooking a simple setting to offset animation on each particle… does such a setting exist?

or does anyone know of a plugin to acquire the same effect

the only alternative method I can think to do this, would be making several versions of the butterfly with slightly offset animation sequences… this seems like a bad way to do it. as it would not obtain the satisfactory result without having a LOT of versions, each with their own particle system… making it slow and making it difficult to change the flapping cycle later on…
I think you will have to create a number of variations, then add them to a group. Instead of using an object as the boid, use the Group. You can then set the blender to pick a random choice from the group for each boid or set the relative proportion of each object in the group. You would just need the one particle system, not one for each variation

ok thanks… I will try this… it would be awesome if there was a way to modify a single object using the NLA editor, but my knowledge of using the NLA isnt great