BPE will have some degree of modularity, in fact the light vehicle deck could be adapted like a prolongation of the hangar, more room for troops would be provided taking space from the light or heavy vehicles decks, the same for hospital facilities. When she operates like a carrier the maintenance facilities from PdA (and the personnel) will be incorporated (Spanish Armada only has personnel for one VSTOL wing onboard). The command facilities will be ever onboard and are comparable if not larger than in L-52 Castilla or R-11 PdA.
Of course, if the ship is operating like STOVL carrier amphibious operations are secondary (and use the LCU deck clearly not recommended).
Spanish Armada seems confident that BPE will be a decent carrier platform not so different of PdA, with the very exception of speed (21 kn. vs. 26), but that only will be ensured once in service.

Regards