Change of basis matrix notation confusion

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I've got strange notation of change of basis matrix in my book and I'd like to have it explained a little bit. It says, if:

$M _{\mathcal A}^{\mathcal B}(id) \cdot \vec{v} _{\mathcal B} = \vec{v}_{\mathcal A}$

then $M _{A}^{B}(id)$ is change of basis matrix from the basis $A$ to the basis $B$. It completely breaks my intuition, because in the result, we have a vector represented in the basis $A$!

On same page in this book, they say: $\phi(\vec{v})=\vec{w} \iff M _{\mathcal B}^{\mathcal A}(\phi) \cdot \vec{v} _{\mathcal A} = \vec{w}_{\mathcal B} $ It brings even more confusion.

Any help would be appreciated.