I received the same email but hours later got another response from HTC online store:
"
Thank you for contacting the HTC America online store.
We apologize for the inconvenience; unfortunately the product that you
ordered is currently out of stock. Although we do not have an estimated
arrival date, we are working to obtain more stock as soon as possible.
As soon as we receive your product, your order will be promptly shipped
and you will be notified via email. Rest assured that if you purchased
using a credit card, we will not charge you until the product ships.
On the other hand, we understand that you have seen that the item is "In
Stock" however the ADD TO CART button is no longer highlighted. We have
tried to place an order on our end and we could no longer complete an
order for HTC ONE M9 and one of the possible reasons may been because of
not having enough inventory for it.
We have already informed our technical center to update the information
on our website to avoid confusions.
"
I don't know if it's really out of stock at this point because I still can add the unlocked silver M9 to the shopping cart on their site without problem, it's really confusing situation though.
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