You can transfer the cam-plus subscription to any camera anytime as long as that camera is on the same account as the original camera.
Let’s say you have a WYZE account with a cam-plus subscription and a family member has a separate WYZE account. There is currently no way for you to take the cam-plus subscription on your account and transfer it to your family members account.
You can’t even buy a cam-plus subscription as a gift for another WYZE user unless you logon to their account and pay for the cam-plus subscription. Which is why I created this wish list item: Gift cam-plus subscriptions