Studio changes are coming to 30 Rock.

WNBC/Channel 4 is going downstairs from its studio on the 7th floor to studio 3C, the home of NBC Nightly News with Brian Williams.

A WNBC spokesman confirms to FishbowlNY that 3C should be ready for the conversion from network to local by year’s end.

“Nightly News” stays on the 3rd Floor, calling the larger 3B its new home, which will include a set for Williams’ new newsmagazine Rock Center, debuting October 31.

NBC’s long-defunct soap opera, The Doctors, originated from 3B during its 20-year run.

WNBC is the latest station to make studio renovations, or get new facilities altogether. Earlier this week, FishbowlNY showed you WCBS/Channel 2′s new state-of-the-art studio tomorrow.

WPIX is also planning to roll out a new studio in the coming weeks.

And last month, WABC/Channel 7 started the wave, creating a street-level studio along Columbus Ave.