It's only a pilot, which means it may or may not go into production as a series. If it does go to series they usually don't start filming until mid-summer. His contract with NBC could allow him to also film GG as well as movies or tv show guest spots prior to filming the series.
I don't expect some characters, like Jess, to be in too many scenes in the Netflix GG series, so he can work it out if need be.