Never, ever, transfer off primary until the gravity is constant. Your yeast will still be in there and they will still be active even if you do, but you risk slowing the fermentation or possibly stalling it completely.
For what it's worth - In my experience my own lagers need about 3 weeks at 50F.
So your hunch was right! The rest of your plan sounds solid. Just be patient with lagers, that's my only other advice. It's a different animal.
In Process - Russian Imperial Stout, Nelson Sauvin Rye IPA, Mild No.3
In Kegs - Barley Wine, Apfelwein, Wild BlackBerry Wheat, Coffee Oatmeal Porter
Gone - so many :(