Question for Gitlab: Why did you collect an email address from the user in the first place? Why does it exist in your db?
Now explain why it was not used for it's only legitimate reason for existing in your posession, first, let alone followed up with a few updates as the deadline got closer.
You have a communication channel that not only is good for this, but exists for this exact sole purpose in the first place. If you aren't going to use it for that, then you have no legitimate reason to have it and I want you to delete it.