What version of QPTL should I use?

The current version of QPTL is v2016A.1. This version of QPTL is based on Revenu Québec publication TP-1015.F-V - Formulas to Calculate Source Deductions and Contributions Effective for payrolls beginning January 1, 2016. Revenu Québec usually publishes updates for payroll deduction formulas once a year, effective January 1, and QPTL is updated accordingly. New versions of QPTL are usually made available for download by authorized licensees within seven days of Revenu Québec's publication of an updated TP-1015.F-V.