The insurance referred to is called Permanent Health Insurance (PHI). Delay before payout can be 4, 8, 13, 26,52 or even 104 weeks, the shorter the delay before payout the higher the premium, premiums also increase with age. Short deferred payout policies are VERY expensive.
If you do look into this check and ensure you understand the small print, most policies are "reviewable", i.e the premium will increase every five years (often doubling) up to your selected retirement age.
The biggest cause for dispute with this type of policy is alleged non-payment by the insurance company, usually because of alleged non disclosure of an existing medical condition by the policy holder.
I wish Graeme a speedy recovery of course, this is a reminder to us all, how long could we last financially without working if we have a more serious accident?