Good catch - I just noticed the different links as well.
I just got 2 notifications with links to 2 different domains, and one with, and one without https.
Redirection to HTTPS and the preferred domain can be done with .htaccess (worse case scenario).
I presume that redirecting in .htaccess will "force" users to the right domain, and enforce https.
This in turn will then automatically resolve the links in the email issue.
I'm using this on my own website to enforcing https:
RewriteEngine On
RewriteCond %{HTTPS} off
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
A quick look with Mr.Google gave me
this for domain redirection, but I have never used it;
Options +FollowSymLinks
RewriteEngine On
RewriteBase /
RewriteCond %{HTTP_HOST} ^OLDDOMAIN\.com$ [NC]
RewriteRule ^(.*)$ https://NEWDOMAIN.com [R=301,L]