Breaking Bug? Comcast Webmail Frontend request to /api/mail returns stagnant data

It appears that when attempting to refresh the web-based mail client, calls to https://connect.xfinity.com/appsuite/api/mail returns stale data. This results in not being able to access new emails via Xfinity Connect. However, SMTP + IMAP appears to still be working fine as emails can still be sent and accessed via direct access to these edpoints from third-party software. The only recent change that could have triggered this was the addition of 2FA securiy to the affected account. However, even after removal new messages do not display in the web UI. Directly calling this endpoint via curl confirms my suspicions that this isn't simply a browser issue.