Can this simulation sequence be achieved

Hello

I want to achieve this simulation sequence with particle replacement API please tell me if it's possible to achieve this

I have a particle p1 generated at position x0 y0 z0

This particle is moving downward in a direction.

Now after the bond time t1 is reached the particle diameter will change from d to 0.9d

And another particle p2 with diameter d will be generated at t1 position x0 y0 z0 and this will be moving downward

Now as 2*t1 is reached the diameter of particle p1 will become 0.8d

For particle p2 also as 3*t1 is reached the diameter will be 0.9d and for particle p1 the diameter will be 0.7d.

Similarly I will keep generating 5 particles of diameter d at position x0 y0 z0 as bond times t1, 2*t1 , 3*t1....5*t1 are reached. And as it moves downward I want to reduce the diameter of the particle.

Please tell me how I can achieve this with particle replacement API or is there any other better method than this API?