The 1-hour licensing interval has been in the SELECT contract for as long a I can remember it just wasn't really enforced so long as the structural products required license checkout via the IEG License Layer.
The SELECT Server Product Activation forum has a lot of details and Q&A:
communities.bentley.com/.../275813.aspx
The Bentley.com website has more of an overview: www.bentley.com/.../Pooled+and+Trust+Licensing.htm