It's on June 28, according to a YouTube video on Scratch by @ceebee I saw. Is it a bad thing? NO! It's a good thing! The original colors we're still using until June 28th will still be an option after the new block colors launch though (But it's not bad news, if you don't want to use the high contrast ones you could change them to the original ones, but I'd prefer the high contrast ones)
Credits: Logoverse-DR4, Daniel-Ette, Danielle and Everyone (also including Ceebee cuz she made the video on YouTube, you could go to the 'Discuss Scratch' page, or YouTube)
