I am writing this question for a friend of mine.
He had sent a job application to a Japanese company. They were in contactfor several months, asking for tests, Skype interviews and written assignments. At some point, three to four months later they even asked him to take the N4 Japanese language exam (they created a customized test and my friend passed it).
Finally about a month ago, they extended what they said was "an unofficial job offer", claiming that they would begin preparations with the Visa process and give him the official start date when the Visa is approved.
They subsequently asked him if he was available to do some tasks for them while the Visa process continued. They then asked him to do tasks not quite related to his job field (my friend is a game developer, they asked him to do some art models or something).
I am afraid they might be pushing him to quit, or decline the offer. My friend has already started selling his stuff to gather money for his trip and immigration to Japan. If they do not actually hire him, it would be destructive for him.
How could he defend against something like that happening. I am worried because of the wording they used for the job offer. Could it not have been an official job offer, with an open starting date?