You will have personal guarantees in place with the insurers. I do with mine.
I am a limited company and I am still liable for any clawbacks personally in the event my company can not pay.
If a claim is made and the policy pays out and then ends, you are not liable for any clawbacks. It is only if the customer cancels the policy or stops paying the premiums.
If the customer can not afford the monthly premium... why did you sell the policy to them in the first place? You can just flog a load of policies and then close down when they start getting cancelled.
In 7-8 years, I have only had 2-3 cancellations in the claw back period. I also used to be an account manager for a life insurance company and clawbacks really were quite rare, probably less than 5% for most companies. As Mark says, this should not be a major concern.