How long does it typically take timber framers to get a building under roof?

I started my first timber frame 5 months ago.
The whole thing (frame and T&G panelling) is EWP.
I'm not using SIPs, and am doing most of the work alone. So it's going slowly, and I'm concerned about exposure to the weather.

The folks who sold me the frame have been a little casual about this. They say people build in all kinds of weather and it's unavoidable that buildings get rained on.

I now have the whole thing covered in T&G, and a 6 mil plastic vapor barrier over part of it.We hardly had rain all summer but now we're getting a fair amount. I hate to apply more vapor barrier until everything's pretty dried out between rains.
Or am I better off getting it covered and counting on the wood drying from the inside?