Still at least a month until he returns so no need to rush any decisions now. Answer might be clearer after all those games until then.
It all depends on injuries/form/opponent. Having Pedri back will give us another dimension and hopefully will increase the level of his competition further. Schedule is tight so there will be plenty of playing time for everyone.
Besides, there aren't many top sides which have a clear starting midfield 3/4. City have players like Rodri, Nunes, Kovacic, Foden, KDB, Bernardo, Alvarez as options for their three central positions. Madrid have Modric, Kroos, Tchou, Cama, Valverde, Bellingham etc.