@Charlaquin @Maxperson @Xetheral @Rune @MarkB It looks like all agree that a requirement for 6 hours sleep is perfectly clear, and given we know a sleeping character has the
unconscious condition I assume we all agree that they can't do any kind of activity in that 6 hours. Not light activity, not strenuous or adventuring activity. Certainly no fighting, no spell casting, no marching! So my question is - for the rest of the time is it really worth quibbling over whether an activity is light or strenuous, and runs for an hour or for two hours!? Why not just rule it like this -
A character gets the benefits of a long rest at the end of any 8 hour period in which they had positive hit points and slept 6 hours. They can't get that benefit again for 16 hours.
[Optionally] A period of sleep must be unbroken for at least 2 hours to count toward this.