Slight Delay

I won't be reviewing a volume of "Our Name in History" (Ancestry.com's latest offering) until at least November 9th. I got an email from Amazon saying their estimated delivery date had changed. (Which is a good thing. I like being told, as opposed to sitting, waiting, and wondering where it is.)

WHY WAS THE DELIVERY ESTIMATE CHANGED?
While we do our best to adhere to these estimates, our inventory is constantly changing based on information we receive directly from our suppliers. Occasionally, unexpected fluctuations in supply or changes in release dates for new products will add time to our original availability estimate.

Since this is a "Print-on-Demand" book I assume its not a fluctuation in supply. I assume its a fluctuation in release date. Since I did put an order in on the day the books were announced, this isn't too surprising.