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I discuss the relation between the d-dimensional BCFT and CFT+gravity descriptions of double holography. In both descriptions entropies can be computed using the RT formula in a (d+1)-dimensional bulk. I point out that standard assumptions about entanglement wedge reconstruction suggest that the homology condition for RT surfaces depends on which of the boundary formulations is taken. It then follows that the von Neumann entropy of a subregion in the BCFT is computed by using the island formula in the CFT+gravity description. Vice-versa, the von Neumann entropy of bath subregions in the CFT+gravity description is a coarse-grained entropy in the BCFT formulation. I also briefly discuss how operators map between both boundary descriptions. Simple bath operators are identical in both descriptions while some complicated operators in the BCFT map to local operators in the island. It is then tempting to speculate about implications for the relation between semi-classical and quantum gravity in d>2.