Illaoi's E Bug/Oversight

As Illaoi, when you make an enemy a vessel, they have to (help) kill three tentacles or wait one minute for the debuff to expire. This is fine. However, if the enemy has only one more tentacle to (help) kill before removing the debuff and you reapply vessel, they still only have to kill one to remove it. The timer is reset to one minute, but the "tentacles remaining" counter doesn't change. I can't imagine this is anything but an accident, and it can be very frustrating to make someone a vessel, only to see them remove it after killing one tentacle. Thoughts?

*This has happened to me on several occasions. I am not sure that it happens every time, but it feels like it.