The Undead warlock patron option found in Van Richten's Guide to Ravenloft includes the following text in the description of its level 1 feature "Form of Dread":
You manifest an aspect of your patron’s dreadful power. As a bonus action, you transform for 1 minute. You gain the following benefits while transformed:
- You gain temporary hit points equal to 1d10 + your warlock level.
- Once during each of your turns, when you hit a creature with an attack roll, you can force it to make a Wisdom saving throw, and if the saving throw fails, the target is frightened of you until the end of your next turn.
- You are immune to the frightened condition.
[...]
The feature doesn't state that any conditions under which it ends before the 1-minute duration is up.
Is it possible to use this feature again to enter the state again before the minute is up (despite already being transformed), in order to gain temporary hit points again?