There appears to be a rather serious system error that’s causing this. Currently we don’t know if eBay will be able to reinstate the missing listings or if users will be left to relist themselves once the error listing limits are lifted.
One thing that we do know is that if your listings have been affected your probably going to have to do a full stock check and verify the quantities on all your listings, regardless whether eBay reinstate your listings or if you have to relist manually.
Another serious issue is of course loss of Best Match score and Sales History on cancelled listings.
Have your listings been affected? Let us know if you have any more information
Email from eBay
We’ve noticed you’ve exceeded your monthly selling allowance. Because of this, your most recently listed unsold items have been removed and all associated fees have been credited to your account. Selling allowances are put in place to help you establish a positive selling history and provide excellent service to your customers.
The removed listings will be available in your “Unsold Items” section in My eBay. You can relist these items by adjusting your current inventory.
For further information, or if you want to have your selling allowance reviewed, please contact us
We appreciate your understanding and cooperation.
21/3/13 Edited to add: Latest update emails from eBay
We’re writing to let you know that as a result of a software issue on Wednesday, March 20, you may have mistakenly received a notice from eBay that you’d exceeded a maximum number of allowed listings. As a result of this issue, some of your listings were ended and some may have been temporarily hidden from search results.
Rest assured we take these situations very seriously. Our teams have been hard at work around the clock to rectify this quickly, prevent any reoccurrence, and ensure your uninterrupted selling. We appreciate your patience and apologize for any confusion or inconvenience this may have caused.
The software issue was fixed within a few hours. Any hidden listings are now restored to view. We are in the process of relisting these listings for you—with a fresh start date and for the same duration. This will not have any adverse impact your standing in Best Match search or your seller feedback or standards.
Please note that if you have already relisted any of these items on your own—and you are free to do so—eBay’s automatic relisting actions will not cause you to have a duplicate listing.
We also apologize if you experienced any delay in reaching our customer support. We will get back to you shortly with an update on the actions we’re taking.
Again, we apologise for any inconvenience. As always, thank you for selling on eBay.
The eBay Selling Team