Honestly I'm not surprised, we have people who wonder why AGG can't be special summoned when it's literally written as the very first sentence on AGG's card text.
It doesn't say 'this turn'. It says you can only use once per turn, but not that it wears off at the end of turn like Ties which are completely different things.
So this skill stacks when you use it in different turns. I tested it just in case.
The above comment were written when the skills had only just been leaked. The leaked version had 'This turn' at the beginning, implying that it was only temporary.