HI,
We have just upgraded from a 6 to a 6P, and thought that we would take the opportunity to check this.
The poles are _not_ the same - On the 6, the joints on the main poles are curved with a flattened side - on the 6P, the joints are squared.
In addition, the curved roof pole follows a different line, with the 6P's being wider and flatter.
Having said all that, we did not attempt to pitch the 6P with the poles from the 6, but we don't think that you would be able to get a 'neat' pitch given the different shape.
In addition, the 'rain-safe porch' appears to be bigger and has a new pole with two angled bends in it rather than the hoop used on the Montana 6.
While the original question is probably no longer relevant (auction finished - we were watching it too!), we hope that this helps someone in the future.
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