The exchange ratio is 1:1 and all will be turned into moon coins but it seems there is a limit to how many you can get in a day/week depending on your level so some coins get turned into the shell looking currency that you can see in the shop instead of moon coins

So that shell looking currency is gotten only when you pass the daily/weekly limit? If so then is the rate 1:1? Also @Sahiku had pics showing Go, Fukurokumaru frags for 2 different currencies, was that a correction or is it really possible to get from both?

500 cave keys maximum daily?

Let's say you have 100,000 summon coins and 1000 group coins, those coins are left alone while arena, survival, and ranked are all considered to be moved towards sun or moon coins. So after the update, summon and group coins are left as it while how many coins in arena, survival, and ranked are put together in either sun or moon coins meant to be spent on the scroll system or the item shop.

That was like that in China but they used survival as well in a later update.

so the survival points stay the same or some are transformed to moon coins?