One gets a flavor of things planned from footnote 5 of a Senate report which includes Mark Lemley and Jaffe and Lerner, among others.
Post-grant review ("PGR," aka opposition) appears on pages 21-22 of the Senate report.
The infamous "second window" is present (unlike in the last version of HR 1908).
There is some great double-talk in the first full paragraph on page 22. The existence, authentication, availability and scope of evidence must be shown by clear and convincing evidence BUT invalidity is shown by a preponderance of the evidence. Who wrote this stuff?
There is an estoppel provision to prevent multiple PGRs filed by one party, and to preclude later litigation on any ground raised in the PGR (but not on other grounds).
There are some funny comments (ie, myopically one-sided) that really have to be read to be believed.