My guess is your death benefit is fully accelerated by the CI rider.
PLLLLLEASE take a look at the T&Cs. I think in most policies, there will be clauses to say that CI claims must be made within 6 months from diagnosis.
Personally, I think since you have paid for the CI rider to accelerate the death benefits, if you are already eligible to claim, just claim. With the payout, you are free to use it for your medical fees, or invest to continue to grow the pot. The death benefit, at best, will continue to grow at <4% per annum, so it is better to DIY and invest it yourself.
In addition, don't forget AIA can always cut the terminal bonus in future and so even if you choose to continue the plan, your death event payout might also be reduced.
Make sure you have your LPA and WILL setup and ensure whatever you invest in, can be easily/conveniently distributed eventually.