It's not really fair or feasible from the company perspective. The sales are there for many reasons. They can be to: promote certain toys, get rid of excess stock, prepare for new versions of toys, and so on. Also having sales on some items can make customers try an item they were hesitant about; the price seals the deal. I think giving a warning would make customers only focus on favorites instead of exploring as well. To ensure the most consistent sales, giving a heads up for people would almost certainly cause issues.

I would suspect that such advanced notice would make certain toys sell out near instantly, putting many toys on backorder, which is something companies like to avoid.

I understand the need for not tell the customer. However, I would love if there was a more accessible way of finding out when companies are making newer versions of toys. I know there's the manufacturing section on the community page, but I feel something more visible and present would be awesome.