March 18: Prior to 4 p.m., New York time, clubs must exercise options for 2020 on all players who have option clauses in their 2019 contracts. … Prior to 4 p.m., New York time, clubs must submit qualifying offers to their Restricted Free Agents with expiring contracts to retain a Right of First Refusal/Compensation. … Prior to 4 p.m., New York time, clubs must submit a minimum salary tender to retain exclusive negotiating rights to their players with expiring 2019 contracts who have fewer than three accrued seasons of free agency credit. … Top 51 Rule begins. All clubs must be under the 2020 Salary Cap prior to 4 p.m., New York time. … All 2019 player contracts will expire at 4 p.m., New York time. … The 2020 league year and free agency period begin at 4 p.m., New York time. The first day of the 2020 league year will end at 11:59:59 p.m., New York time, on March 18. Clubs will receive a personnel notice that will include all transactions submitted to the league office during the period between 4 p.m., New York time, and 11:59:59 p.m., New York time, on March 18. … Trading period for 2020 begins at 4 p.m., New York time, after expiration of all 2019 contracts. Note: This is the big day. The Dolphins have four impending restricted free agents on their roster — LB Deon Lacey, S Adrian Colbert, LB Vince Biegel and P Matt Haack. The Dolphins did not extend qualifying offers to any of their restricted free agents last year, though they ended up re-signing linebacker Mike Hull to a two-year deal.