Generally group buys run for several months.
This one, for example, elton has to collect all the money (let's hope everyone pays on time), send the money to Tai Hao, Tai Hao have to get into gear and actually make, sort and send the keycaps.
Then elton has to separate them into each order, and then post each order to either the proxy or the individual.
This could take another couple of months before all sets are distributed, especially considering the huge volume that was ordered.
Occasionally a "turbo" GB takes place, where orders are taken and payment collected within a couple of weeks. But for the most part, expect a GB to run for at least 2 - 3 months.