Vested options and RSU: rollover

Hi guys,

Say you want to acquire a business and most employees have received SO and some have RSUs:

- can these be rolled over in an acquisition process? 

- how do you structure these? (vested options & RSUs are deducted from sahre count and contribute to sources?) 

- employees with vested options shall be issued options in the new entity. How do you account for this in a model? 

- how do you communicate on this to the employees?

Thanks!