Erect-crested Penguin?

This weekend while showing a non-birding visitor the sights of Victoria's Great Ocean Road we happened upon an unusual penguin on the beach immediately north of the 12 Apostles viewing platform. We tentatively identified it as an immature Erect-crested Penguin, mainly based on the pattern on the underside of the flipper, but none of my guide books show the immature plumage of an ECP. (Slater et al,Simpson & Day, and Harrison). There had been very strong winds from the SE the preceding day and night.