Robert Harington, in a new Scholarly Kitchen post:

The Plan S transformative agreements have essentially created institutional lock-in businesses on a grand scale. Only publishers who have significant publishing scale may effectively form transformative Publish and Read agreements with institutions (a category that can include governments). This is a problem, not just for societies looking to be as open as possible, but even for fully open access publishers such as PLOS. As Alison Mudditt (CEO of PLOS) recently pointed out, if you are already in full compliance with Plan S you are essentially shut out of the monies attached to transformative deals as publishers move from subscription to gold open access.

It’s a good point about scale and read-and-publish deals. The reference to PLOS, though, raises an even bigger problem, one that plagues the various subscribe-to-open initiatives too: If current library budgets are diverted to flip the existing gated content to open, where will funds come from to support existing OA initiatives like PLOS? The answer can’t be APCs.