I saw on the homepage that The Guardians of the Galaxy Holiday Special is currently labeled as "unknown phase". I originally thought this was because the Special Productions were not listed in the most recent official slates however Werewolf By Night is included in the phase 4 list so based on its release date of December this year we have two options.
Place it as the final instalment/epilogue of phase 4 similar to how Spider-Man: Far From Home is the epilogue of phase 3 despite thematically fitting better in phase 4
Place it as the beginning meaning that Black Panther: Wakanda Forever is the definitive end of phase 4 but saying that Ant-Man and the Wasp: Quantumania is not the start of phase 5
