I think there seems to be some confusion here

We need to identify the type of insurance we are talking about

Personal Accident (PA) and Hospital & Surgical (H&S) are considered annually renewable policies
unlike the other life policies. That is to say, the "renewal" is annual, be it a stand alone or a rider attached
to another policy. This is important because, except for the above 2 policies, what matters is
what is material WHAT WAS TRUE AT THE TIME OF APPLICATION

On the other hand, a smoker who pays smoker rates and later stops, can appeal to the company
for non-smokers rates, and the insurer can consider based on length of non-smoking, doctor's report (your cost!), etc

For PA, especially it is different. PA is a renewable policy, where Occupational Class and risk is important
The insurer will not be concerned if you smoke or not. They are more interested if the job risks have increased

Example Clerk - Class 1, Lorry Driver - Class 4, Lumberjack - Class ?? (decline coverage). Note that
the insurer will take your money for renewal every year, it is only during claim that these issues will crop-up and you
might feel "cheated" when the insurer was actually correct in treating it like that. Then there are also exclusions
of some insurance policys. Eg some policies don't cover death due to fumes or poisioning, scuba diving, mountain climbing... one or two don't even cover if you have an accident on a motorcycle

Just because you don't fill up a form every year, don't think the insurer must accept your renewal every year
They can turn around and say that they don't want to sell the PA anymore and not take your money

H&S is actually a grey area, now with insurers giving Guaranteed Renewal. It will depend on the policy terms and conditions as to whether your job will affect your insurability

Please take note, that in all aspects of insurance, a policy holder cannot be reckless, or partake in any illegal activity
not be covered for any cosmetic activity ( because it is not really necessary) or be not covered during war

Will your life insurance pay if you got shot by police in a robbery?... are a soldier who died in a war?.... lost both your legs because you stepped on a landmine? Please get your insurance agent to reply you and share in this forum. It will be interesting to see the answers. Although you have a critical illness insurance, the insurer will not pay for your liver damage because of alcohol abuse

On a final note, should a policy lapse due to non-payment and you revive (reinstate) it again, then the "new / present" are important now. The insurer can refuse to reinstate or can load you due to riskier situations
Eg charge you loading because you have hypertension or you smoke know