The optimum conditions for access and sustainment of H-mode plasmas and their expected plasma parameters in the Pre-Fusion Operation 1 (PFPO-1) phase of the ITER Research Plan, where the additional plasma heating will be provided by 20 MW of Electron Cyclotron Heating (ECH), are assessed. The assessment is performed on the basis of empirical and physics-based scalings derived from present experiments and integrated modelling of these plasmas including a range of first principle transport models for the core plasma. The predictions of the integrated modelling of ITER H-mode plasmas are compared with ITER-relevant experiments carried out at JET (low collisionality high current H-modes and ASDEX-Upgrade (significant electron heating) for both global H-mode properties and scale lengths of density and temperature profiles finding reasonable agreement. Specific integration issues of the PFPO-1 H-mode plasma scenarios are discussed taking into account the impact of the specificities of the ITER tokamak design (level of ripple, etc.).