In an email that Google has been sending out to Project Fi customers who pre-ordered the handset, the company stated that the phone had been delayed due to production and that it will only be shipping in the later part of October, as opposed to around now where customers were supposed to receive it.
The email reads, “Thanks for ordering a new Android One Moto X4 from Project Fi. A production delay has impacted the estimated ship date for your new phone, and your device should now ship between 10/18 and 10/25. You’ll receive a separate shipping confirmation as soon as your order ships.”
It is unclear if this estimated shipping date is applicable to all customers, or if different customers might have received different dates, but either way it looks like the handset’s release is delayed. If you haven’t received the email then you should probably check to make sure as you could be part of the delay as well.