In power generation plants, many critical components are subjected to complex tension-compression cyclic loading followed by long-term creep dwells. While uniaxial creep behaviour of components is well understood, there is limited understanding about the effects of cyclic deformation on the creep, particularly with respect to the grain scale anisotropy. We propose to use in-situ neutron diffraction to measure the evolution of grain-scale misfit stresses during cyclic loading and those effects on the subsequent creep stress relaxation introduced at different locations of the cycle. The experimental data will enable us to validate a novel crystal plasticity based micromechanical model capable of predicting the creep behaviour of engineering systems in realistic conditions.