Avoid driving through Mikoajki between stages, if u have to, remember there are huge traffic jams so give yourself some extra time. Talking about accommodation, last year locals weren't very aware of rally so u could easily get nice place in normal prices even few days before start. This year may be little different but still nothing to worry about. And Mikolajki is not the best place to sleep because of those traffic jams. I'll do the same as last year, take my tent and sleep on stages that's the way to feel beauty of Warmia and Mazury