BUG on Oath of vengeance of Grafted blade greatsword

[月亮吃星星]

After the DLC update, use the skill oath of vengeance multiple times can NOT refresh its effect time.
All the effects, all stats +5, poise, taken damage reduce, can only take effect again after their already-existing effect time is over, even if you use skill and cost FP/Stamina.
It can be easily reproduced, just equip Grafted blade greatsword and use skill: test for 60s all stats up, use a first time and start counting 60 seconds, then use skill again and again within this 60s. you'll find no matter how many time you use skill, the stats up effect is gone after 60s counting from the first time use.
Each effect is separately counted, which are 60s all stats up, 5s poise up and taken damage reduce. So for 5s effects it can only be re-gained after their 5s are gone. Meaning you will get NOTHING if you use skill again within 5 seconds, but FP and Stamina are truly spent. I don't think all of these are intended for update, at least a skill should never cost you FP but give nothing.

[月亮吃星星]

I'm a Grafted blade greatsword lover and I'm pretty sure effect time can be refreshed during existing effect time, before DLC update.
Still think this should not be an intended nerf, so far this is still the case in 1.12.2.