48h wait before playing guild challenge

Why is there a 48hr wait before you can take part in a guild challenge? I'm in the challenge, but when I go to play a match, I get a pop up stating that I need to wait 48hours? Bit annoying, is there any reason?
It's a good change, people were hopping 8n and out of guilds to play certain guilds.
We had a challenge a few seasons ago against a guild that only had 13 teams 3 teams were high star the other 10 were around our star rating after the challenge was started we then found they had 10 more high star teams join the guild who all were upgraded to experienced who all played in the challenge we got creamed the new rule stops this so its a good rule