When to pick Hyacinth Beens 4 seed?

Hello friends.
My wife has Purple Hyacinth beans that are covered with seed pods but I can tell by looking through them that the beans aren't at the size the seed beans were. So, how long should we wait before pulling them and are there any signs that indicate when they are ripe for picking?
I sure hope they ripen before we get a freeze. Will a freeze or frost hurt the viability of these beans?
Any info would be greatly appreciated as we've taken quite a liking to this vine. I can't believe this is the 1st year we've ever grown them.
Thanks, JD

I usually pick mine next month though there are some pods mature enough to pick now on my vines. You can usually ascertain maturity when the pod is brown. I get self seeded volunteers every year but not many (for the actual amount of seeds that are produced yearly).

jmorth
So the outter jacket around the seeds will literally turn brown? Man mine must have quite a ways to go as I've never seen a brown one yet.
Man it's a very good thing I asked this question(and a great thing you answered!) as we just about picked a bunch of them that are all deep purple still.
Thanks a bunch!
JD