I'm looking at a base model with an upgrade to a SSD - Apple site is saying Oct 25-27 delivery. Is this just under-promising or is it really taking them over a week to ship?
That sounds about right. I just ordered a BTO 27" iMac (3.8GHz i5, 16GB 2400MHz DDR4, 2TB Fusion) on October 11. It shipped (from Sunnyvale, CA) yesterday and is scheduled to deliver UPS on October 18.
B&H Photo offers the same customized Macs with SSD and loaded out RAM. They ship faster than what Apple is offering. Here are all the 27 inch versions at B&H Photo: