The End of Shadowbringers? (Possible spoilers)

[Edax]

5.3 is being touted as the end of the story of Shadowbringers. Does this mean we can't expect any more major content patches until the next expac? Or will it be like with Heavensward, where the story of Ishgard ends partway through the 3.X content cycle, but continues with the introduction of the First's Warriors of Darkness and the events leading into Stormblood?

Seventh Umbral Era Quests – Level 1-50 story quests released in Patch 2.0 as part of the base game A Realm Reborn.
Seventh Astral Era Quests – Level 50 story quests that continue the A Realm Reborn story through Patches 2.1-2.5.
Heavensward Main Scenario Quests – Level 50-60 story quests released in Patch 3.0 with the expansion Heavensward.
Dragonsong War Quests – Level 60 story quests that continue the Heavensward story through Patches 3.1-3.5.
Stormblood Main Scenario Quests – Level 60-70 story quests released in Patch 4.0 with the expansion Stormblood.
The Legend Returns Quests – Level 70 story quests that continue the Stormblood story through Patches 4.1-4.56.
Shadowbringers Main Scenario Quests – Level 70-80 story quests released in Patch 5.0 with the expansion Shadowbringers.
Post-Shadowbringers Main Scenario Quests - Level 80 story quests that continue the Shadowbringers story in Patch 5.1. This is the current ongoing set of quests.