User blog comment:Phantom R/Sonic CD re-release trailer hints for Sonic 4 Episode 2/@comment-4018912-20110826005001

I wouldn't doubt it. I mean, seeing the opening with the Sonic 4 models, it seems highly likely that Episode 2 might have elements from CD. I'm hoping they return the Time Travel part of CD, but not the special stages. I've played those Special Stages, and those UFO's move away a tad too easily.