This is a case of a petal peloric Phal (first one I've seen!). Orchids have 6 tepals: 3 are sepals, 2 normal petals and 1 special petal - the lip. In petal pelorics, the two normal petals exhibit features typically only found on the lip. This can vary from just some of the patterning to a complete replication of the lip (which seems to be the case here).