Potion of heroism: wording and timing

Question

Me and my friends (as non-native english speakers) are having trouble getting the timing of Potion of Heroism. I copy the relevant text for reference:

For 1 hour after drinking it, you gain 10 Temporary Hit Points that last for 1 hour. For the same Duration, you are under the effect of the bless spell (no Concentration required).

The problem is in the first sentence. We don't understand why "1 hour" is mentioned two times, first related to the effect (gaining THP) and then related to the duration of the THP themselves . Currently we have two interpretations:

1. For one hour after drinking this potion (as an action), you can choose to gain 10 THP. These THP will last for an hour.

2. When you drink this potion, you gain 10 THP that last for an hour.

If it's case 1, it's unclear if the duration of the blessing spell starts when the potion is drunk or when the effect is "activated".

If it's case 2, the blessing spell lasts for one hour right after drinking the potion.

I have searched quite a bit, and haven't been able to find any clarification on this, nor anyone complaining about the wording. As a secondary question, is this wording clear and I just can't absorb the meaning properly, or is it a bit ambiguous?

Answer 1

It is clear removing either mention of hour gets you the same results -- Your #2.

For 1 hour after drinking it, you gain 10 temporary hit points that last for 1 hour.

Could be:

For 1 hour after drinking it, you gain 10 temporary hit points.

Which is your #2. Or it could be:

[A]fter drinking it, you gain 10 temporary hit points that last for 1 hour.

Which is still your #2. The duplication must be a typo, as both readings lead to the effects being 1 hour after being drank. There is no mention of activation or using another action.

Answer 2

The wording isn't clear.

To me (a native English speaker), this sounds like it was something that didn't get caught in editing. I think the intended wording is:

When you drink this potion, you gain 10 temporary hit points that last for 1 hour. For the same duration, you are under the effect of the bless spell (no concentration required).

Answer 3

The important thing to note is that Temporary Hit Points are "a thing" in D&D 5e. In particular page 198 of the PHB or in the combat section of the SRD, it states:

Unless a feature that grants you temporary hit points has a duration, they last until they’re depleted or you finish a long rest.

In this case, the temporary HP don't last until you finish a long rest, they only last for one hour. Note that these temporary HP are being granted by "a potion" not by "a feature", so that extra clause is there for absolute clarity.

They could have worded it differently.

After drinking it you gain 10 Temporary Hit Points that last for 1 hour. Also, for 1 hour, you are under the effect of the bless spell (no Concentration required).

But the clarification of the temporary hit point duration would still be there.