Does anyone know the answer to this MA question?

[Veronica Mars]

Sorry if this kind of question has been asked before but I didn’t know where to look.

I was thinking of buying Sommersby on Amazon in hd for $9.99 and dumping the bd. iTunes also has it in hd so it would port there but vudu only has it for sale in sd even though the movie page says they have it In hdx which is quite peculiar.

If it doesn’t redeem in vudu in hdx but, rather, sd, are they obligated to upgrade me to the hdx version when they do have it? Because if it ports to iTunes in hd and vudu in only sd, I don’t want to be stuck with the sd version or have to rebuy it at full price on vudu later.

Thanks for any help with this.