I received an email from Logos advertising updates that will soon be available to add to certain existing collections. The email invited me to pre-order updates. Two of the collections which I have are the Reformation Commentary on Scripture and the Pillar New Testament Commentary.
When I follow the link to the RCS update, my upgrade price is £20.85 despite the individual price of the new (John's Gospel) commentary being £18.94. Similarly, when I click the link to the PNTC update, my upgrade price is £22.62 despite the individual price of the new (James, 2nd ed.) commentary being £20.40.
Anyone thinking about updating their collection may want to check their pricing.