Welcome to the site, Tom!
Is this a good forum for making that connection?
Yes, this is the right forum. And if you are looking to make specific climbing plans post in the Upcoming Trips
Most people plan climbing trips about 1-3 weeks before the trip. Also, if you have a weekend that you want to climb and want to see if others are interested, just post in the upcoming trips and you should get a few bites.
Lastly, fall (in my opinion) is the absolute best time for climbing in Korea. the weather is perfect, cool and dry and climbing is fantastic. Expect a lot more trips to pop up in september and october. July and August are sometimes too hot or too rainy or both.
Hope this helps