Probably never.

Zenos - thanks for your short, but not-so-sweet reply. It may be as you say - but does the Mozilla staff ever respond or weigh in on issues? Or do you need to post your question in a specific forum?

There is a lot happening behind the scenes. The fundamental technology that Thunderbird is built on is shared with Firefox and is being withdrawn by Mozilla. Thunderbird is going it alone under the care of its own Council, who are currently wrestling with many issues about how to keep it alive and more importantly, how to transform it into something modern and maintainable.

With all this going on, and with the shortage of manpower, resources and finances, I can confidently but reluctantly say that enhancements such as the one you ask for are very low on the to-do list. :-(

Zenos,

Thanks again. I understand your explanation - and I wish the Thunderbird folks all the Best, given their situation. I'm also aware that the feature I asked about is offered by very few email service providers. I may need only 2 fingers to count them. And here I'm not including any 3rd party add-on apps.

The funny thing is that, in this 24/7, multi-time zone world, having such a feature would be invaluable.

Best, Jim

People tell me this is a useful capability. I've never been in a position where it would have helped me. If an email needs sending, it needs sending. I don't understand why "when" is so important. ;-)

The Send Later has worked for me in the past, in testing, but you have to understand that to use an email client to send by schedule, you have to have your client, computer and internet connection all running at the point in time when you want it sent.

A Send Later function is very much better handed off to a properly maintained server, with redundancy, UPS, multiple internet connections, maintenance staff etc rather than all the somewhat shaky dependencies around using it on a desktop PC.