Level 50 may need to be changed

[Vandril]

The issue is, you shouldn't see it as wading through, like unblocking a toilet. It's an experience in itself that just happens to unlock Heavensward. You're seriously missing out if you don't just take it easy and enjoy the fascinating story that is ARR.

This. Thinking about the level 50 MSQ as something that blocks your progress toward Heavensward is the wrong way to think. Instead, consider it as much a part of the game as Heavensward is. It's honestly no less a part of the game than any other level's MSQ chain. So, instead of worrying about when you'll finish it, just focus on enjoying it as you play through.