Not on hold, but there was an advisory issued to Distributors that they put stickers on the boxes of existing inventory telling users to check out Knowledgebase ID: 603580. It involves a change done in a previous firmware release having to do with the way the Stop logic is performed when using Network control and a certain set of other conditions. Users employing this specific set of conditions need to be aware of the change.
So the Distributors have been asked not to ship from their inventory until they either flash the firmware, or apply a sticker to the box advising the customers to read that article to see if it applies to them or not. This is not going to apply to a very large number of users because of how narrowly specific the set of conditions are, but it has to be stated. It might be that some distributors are choosing not to apply the stickers, but rather flash the firmware first, which might mean a delay in their shipments from existing inventory.