Actually the Saxe-Coburg Heir is alsoa Prince Hubertus as the oldest son of the present head of the House, Prince Andreas is also named Hubertus.
Did I question that? I am confused by your defensiveness. I said Ernst was not heir, that the Hubertus I mentioned was.
Queen Victoria's son Leopold had one son Charles, who was stripped of the title Duke of Albanny. Charles had five children. His eldest Johan had three children, including the Ernst I assume the original post was about. Ernst would have a claim, except for the fact he is dead. His eldest son, Leopold's great-great grandson is the Hubertus I spoke of. Since the death of his father, Ernst has no claim as he is dead, he is the rightful claimant of Duke of Albanny.
Leopold's daughter Sibilla married into Sweden, and is mother of the current King of Sweden
the third child was Prince Hubertus who died in action without marrying.
fourth was Princess Caroline, married some count, like Sibilla she is female so her heirs don't count
then fifth and last we have Friedrick Josias, father of the Andreas you speak of (one of his many christian names is Hubertus, but last in the list, he is in no way Hubertus as well) and his eldest son is Prince Hubertus, he also has a son and another daughter
So for Albanny not to be extinct there is no shortage of male heirs. Prince Hubertus (the one with the claim) has a son Sebastien. He also has three half brothers from his father's second marriage (2 half sisters from second and third marriage but again no inheritance rights). Ernst also had a younger brother, who had two sons.Then it would pass to the Andreas you spoke of, his son Hubertus, or Hubertus' younger brother Alexander. Andreas also has a younger brother Prince Adrian, who has two sons Simon and Daniel from his first marriage. These are all male line descendents, with a claim, as do any sons they have in the future, so I doubt William will ever be duke of Albanny, unless something like King Ralph happens, and a huge disaster falls the family at a family reunion.