We're finding that the responses to GetOrders (Trading API) with 'modified' flag are intermittently not including orders. This means orders are being missed. It has affected many of our clients yesterday, but we've seen this same problem earlier in the year also.
This is really serious. Anyone depending on GetOrders with 'modified' need to review because you're probably not getting all the orders.
Had to buy premium support to tell them, because these forum posts are rarely seen or answered, even when it's serious. I will update this post with the result of the ticket.
There are two issues, one as described above, and the other just discovered regarding buyer's checkout notes. This may not affect other systems in the way it has us. It is that there are now line feeds being inserted by eBay into the BuyerCheckoutNotes field. The line feeds are not encoded.