In reality, Nebula access for CS subscribers expires on Dec 31st. This means you'll have <2 months out of your "locked in" 2 yr contract. All their communication seems to imply the opposite. If you got a CS account mainly to watch Nebula, I recommend getting a direct Nebula subscription instead.

With the CS bundle coming to an end, it will be the only way to watch Nebula starting from Jan 1st. My link for signing up is go.nebula.tv/techaltar