Any photos and videos you've shared with a Share Group will remain only visible to members of that Share Group after your subscription ends. However, you won't be able to edit Share Groups or share uploads with any of the Share Groups you've made. You will be able to change the visibility settings of photos or videos from a Share Group to the whole album or just Album Admins (but not the reverse). If you resubscribe to FamilyAlbum Premium, you'll be able to share uploads with your previously created Share Groups.