The original timeline for the mission (as of July 2014) looked like this:
As of 19th December 2016, mission adoption has been delayed until June 2017 at the earliest.
Mission launch has also been delayed until 2025.
ESA have slightly reduced the scope of the baseline mission. PLATO will now have 24 telescopes (with 2 additional 'fast' telescopes), and will have a baseline mission duration of 4 years (though a mission extension is still available). No significant impact on science is anticipated.
The PLATO Mission Consortium (PMC) is currently moving towards the end of Phase B2. Both the PDCR and Payload-SRR have passed, with some very useful feedback from ESA regarding various aspects of the PMC setup and progress to date.
In spite of the latest delay to Mission Adoption (see above), work on the Payload continues apace, with ESA advising the PMC to continue to follow the previously planned schedule. There will be unavoidable changes however owing to the delay in the awarding of the spacecraft contract.
Current efforts of the PSM Office continue to be focused on definition of the high-level PSM-PDC schedule, development of the document tree and content management, and defining data processing requirements.