During the migration to the new system, all the existing subscriber addresses were imported. That is why you are currently receiving messages from the list.
However, even if you are currently receiving emails, that doesn’t necessarily mean that you have an account on the new list system.
To manage your subscription settings (like digest delivery, etc.), you need to create an account. Effectively, you’ll be “claiming” the account associated with your email address.
Once you’ve done so, you will be able to manage all your subscription settings as before.
If you have trouble, feel free to contact me off-list.
73, Matt nj4y