asked:
Who does the opinion go like to with whom can you say Musaf with?
The Kollel replies:
The SHULCHAN ARUCH (OC 286:2) rules that Musaf is recited both when one is Davening alone and when one is Davening with a Tzibur. However, one who is Davening alone should not Daven Musaf on Rosh ha'Shanah until after three hours have passed into the day (OC 591:8).