Hi,
Without knowing exactly what the investment is, it is difficult to say but it sounds like you would still be within the chargeable events regime if you still has the same policy with, perhaps underlying investments within it. You would need to consider if anything you do, changes the policy or creates a chargeable event. You can see guidance on chargeable event gains here:
HS321 Gains on foreign life insurance policies (2023)
IPTM3400 - When events occur: general
Your insurance company would be able to confirm if this is the case so you should check with them. If not then you would consider it when the policy matures. You would get a chargeable event certificate in any event.
Thank you