Euro-PCT deadline = Month 31 

July 27, 2016
Neil Milton

The deadline for filing a PCT regional phase application before the European Patent Office is 31 months from the international priority date

Of course, in order to file a PCT regional phase in Europe, you must have first filed a PCT application.  Recall that you can file a PCT application at the USPTO a) before the first anniversary of a provisional, claiming priority to the provisional, b) as the originating application without priority, or c) in parallel with a US non-provisional filing with or without a claim to priority, but a PCT application must meet, either directly or via a claim to priority, an absolute novelty requirement (no 12 months grace period for disclosures by the applicant).