Old items being emailed to subscribers

[Jon Nichols]

I have a few cases where previously emailed items (from 2 or 3 months ago) are being emailed out again to subscribers.

I've checked the actual feed (both the source one, and the Feedburner one) and the items aren't at the top - they're still in the place they were originally. 

Both feeds also show as being valid. 

Looking at https://support.google.com/feedburner/answer/78982?hl=en

What triggers the email to be sent out?

FeedBurner sends subscribers a daily digest of new content from your blog, so a new post, new title, link, or change to the published date will trigger the email delivery. If you do not post anything that day, no email is sent out.

FeedBurner only keeps a change history for items currently listed in the feed. Once they “drop off the bottom” of the feed, the system forgets about them completely. If you re-introduced them later by increasing the number of items your feed contains, this will result in the newly included items being delivered via email as “new” content.

None of those things apply here.

 

[Colette Pairain]

I have regularly the same problem and don't know how to cope with it !  (Twice the last week !)
Hope we shall get some help from someone...