Hi PCI QSA Tribe,
In a recent article, PCI SSC announced the upcoming release of PCI DSS v3.2, and its intention to cancel the 3-year cycle for new versions update, only to stay with “minor” updates to the standards focusing on specific areas – as the PCI DSS is already a mature standard and does not require big modifications anymore.
Therefore there will not be a PCI DSS v4.0 in 2016, most probably even beyond 2016. The only update would be v3.2 which is expected somewhere around March-April. (we're working on that with SSC)