Hi Pippin,
Further to my post in the same thread, I also spoke to an immigration attorney in Canada who has good experience with appeals on PN cases. He agreed that an intention to settle in the nominated province is crucial, at the same he (the attorney) also mentioned however, that plans and intentions can change and are permitted to change after landing, based on real life experiences faced by immigrants in the province.
Also, there is no litigation in the past, not even one that he could find, where a province has taken a PN to court for having relocated to a different province after spending some time in the nominated. This means provinces are well aware of the charter of rights and know that there is no case that can be pursued. There is no guideline on the minimum amount of time but my personal opinion is that one has to provide sufficient time and work with the institutions of settlement in the nominated province, i.e. in summary make a genuine attempt at settling.
Hope this helps.
I also got another question clarified. It is okay to land and get immigration clearances done in some other province for PNs, in case where is no direct flight to any city, in the nominated. However, it is important to have a connecting flight booked, initial stay reserved etc i.e. to have made plans to settle and if required, also show the documentation pertaining to that plan to the CBSA officer at the port of entry.