Per Uncle Bob, the NHL will tentatively begin playoffs on August 1, as long as COVID can be kept under control and Phase 4 of reopening takes place.
If that date doesn’t get pushed back, as previously reported, teams could report to the Hub cities of Toronto (Eastern Conference) and Edmonton (Western Conference) on or about July 26 with meaningful games (Phase 4) to begin play on or about Aug. 1.
— Bob McKenzie (@TSNBobMcKenzie) July 6, 2020
Here is when the Lightning will start training camp, playoff tournament [Bizjournals]
Assuming the league does not run into any major issues, teams are expected to report to their hub cities, Toronto for the Lightning and remaining Eastern Conference teams and Edmonton for the Western Conference teams, on July 26.