Hello aainc,

I also like the idea of ​​automatically detecting custom field data in the subject line of an email. This speeds up the email work and prevents errors. As of this time, we haven't heard an update about this. I would recommend suggesting again by clicking on the Gear icon and choosing Feedback.

Feedback makes our engineers aware of the features that our clients want to see or change in QuickBooks. I believe they receive thousands of them. The feature with the most number of requests will be subject to deliberation and approval and is more likely to get implemented.

New features are usually featured on the QuickBooks Blog page.

If you have other questions or suggestions, feel free to go back to share them with us here in the Community. Take care and more power to your business!