Thats what i just saidI am only thinking logically. Naruto is the meeting place for the tailed beasts. When they meet is when Naruto can use full RSM. Full RSM is characterized by the rinne symbol on his back. TSB is also a feature of that mode.
If u want to stick to flawed logic though be my guest
Only when Naruto is using all bijuu chakra does he gain gudodama, markings,etc. :Sparks: