Repeat saving throws with unspecified timing

[Zhorn]

Noticed this with the Dust Mephit
The blindness afflicted by the Death Burst allows for a repeat saving throw to end the blindness each turn, but does not specify the timing where it is the the turn's start or end.

Being unspecified, I'd be ruling with an end of turn save, since that's what allows the affliction to be relevant for at least one round.
But Still I'm curious if there's a general rule to cover this?

[RogueJK]

To my knowledge, there isn't a general rule, because the timing of a save is intended to be specified for each ability/spell. This was likely just an oversight that made it into print.

I'd rule that it occurs at the end of the turn, just like the text specifies for the saving throw to end the blindness for their other Blinding Breath ability.