+1(514) 937-9445 or Toll-free (Canada & US) +1 (888) 947-9445
No - they can't change their sponsor.
 
They can (not necessarily will) begin the process of revoking your permanent residence if it come to IRCC's attention. You would be in violation of the condition.
 
mimzylou18 said:
What happens in the event of a separation before the conditional period is up?
Potentially IRCC could investigate and revoke the PR status. However, unless they are informed it's unlikely that a random check would catch up with them.