Quote - Short and sweet answer is no, you can't pause dynamic calculations, hair or cloth.

But you can calculate simulation in few parts.

For example 100 frames simulation frames 1-100.

Calculate 50 frames and press cancel. In frame 50 create morph on cloth.

Create new simulation 50-100, in 50th frame set morph = 1. It is possible that in last frame you should set morph = 0, because cloth can be double folded.

You cannot do it with hair simulation, but you can render pasrts of preview window and later join it in picture editing software.