The type-I condition is that for some $C > 0$ we have $|Rm| < \frac{C}{T_{sing} -t}$ where $T_{sing} < \infty$ is specifically the supremum of times such that $|Rm|$ is bounded.
In the type-II case, it will turn out the $T$ you get from your ODE estimate must be smaller than $T_{sing}$. (Indeed, if you just try to get such a $T$ from basic ODE estimatesthis route, it will nearly always be smaller). When $T < T_{sing}$ the estimate you get will not work at the singular time.