Please help with a diagnosis for plant/cones..(Pics)

Hi all....I've posted the links to some pics of my hop plants. As you'll see some of the cones are getting a brownish color that doesn't appear "normal". Also, I the plants seem to be going "yellow" from the bottom working its way up. I don't think that my hops are ready to be harvested yet, I'm thinking in another week or two. I hope I'm not going to lose a majority of my cones before then. Any ideas??? Thanks

http://www.flickr.com/photos/27812994@N03/4895837871/
http://www.flickr.com/photos/27812994@N03/4895838447/
http://www.flickr.com/photos/27812994@N03/4896433952/
http://www.flickr.com/photos/27812994@N03/4895839675/
http://www.flickr.com/photos/27812994@N03/4896435106/
http://www.flickr.com/photos/27812994@N03/4896435606/
http://www.flickr.com/photos/27812994@N03/4896436754/

They look ripe to me, I'd be harvesting.

Disclaimer: I know nothing.

Looks like sunscald.

yellowing and browning on the lower leaves is very common and not necessarily indicative of any sort of disorder. The browning of cones, unless it is just a little browning on the tips of the hot cone leaves, might be an issue, but I am not sure what. I've not had a single cone turn all brown right next to a whole bunch of perfectly green ones.

I have not had any problems with insects at all this year and I don't see anything that would make me think there is some kind of fungus/mold causing a problem. Being a 1st yr grower I don't have the experience to know when the hops are ready for harvest. I've done a ton of reading here and based on that I'd say they need to stay on the bine a little longer.