Absolutely, this should be the bare minimum, and I'm sorry that hasn't always happened in some cases. Personally, I'm of a mind that these delays should be communicated at least a week prior to the stated release date, and that's the kind of minimum I want to work towards (barring last-minute delays of delivery of stock to the UK, which are always their own unique brand of issue).It might not be quite this simple, but can people who preorder from AL directly not just be sent an email on the Friday afternoon before a Monday release if stock is not on-hand at the fulfilment house?
I understand that other retailers will want new dates to update their listings so that should probably come later, but I struggle to think that you won’t be aware the Friday before release if assembled stock is on-hand.
I think Dai is pretty much on the right track that ultimately it's all about processes and having a system in place to ensure the right communications happen at the right time, and that's something for us to work on and improve internally to make these external communications better.