DatapointsSubscription: Expired cursor

I understand that updates older than 7 days may be discarded from the endpoint, which is perfectly fine. However, I’m wondering if it’s possible to determine when a cursor is older than the given limit, since updates older than 7 days are discarded. Based on my understanding of your Subscription API, it would simply continue iterating over the oldest available updates on the endpoint, which could result in missing important updates that occurred between the time of my cursor and the current oldest update.

For the Subscription API to be fully functional, I believe it's essential to either receive a notification or an exception when using an expired cursor, be able to determine the age of a cursor, or somehow be assured that iterating from a cursor won't lead to lost data. Knowing the age of the cursor would be preferable, as it would allow us to gauge how much margin we have, but it should also be possible to receive a notification if an expired cursor is being used.

Is this currently possible, or are there any plans to implement such a feature?