  Underlying disorder in skyrmion materials may both inhibit and facilitate
skyrmion reorientations and changes in topology. The identification of these
disorder-induced topologically active regimes is critical to realizing robust
skyrmion spintronic implementations, yet few studies exist for disordered bulk
samples. Here, we employ small-angle neutron scattering (SANS) and
micromagnetic simulations to examine the influence of skyrmion order on
skyrmion lattice formation, transition, and reorientation dynamics across the
phase space of a disordered polycrystalline Co$_{8}$Zn$_{8}$Mn$_{4}$ bulk
sample. Our measurements reveal a new disordered-to-ordered skyrmion square
lattice transition pathway characterized by the novel promotion of four-fold
order in SANS and accompanied by a change in topology of the system, reinforced
through micromagnetic simulations. Pinning responses are observed to dominate
skyrmion dynamics in the metastable triangular lattice phase, enhancing
skyrmion stabilization through a remarkable and previously undetected skyrmion
memory effect which reproduces previous ordering processes and persists in zero
field. These results uncover the cooperative interplay of anisotropy and
disorder in skyrmion formation and restructuring dynamics, establishing new
tunable pathways for skyrmion manipulation.
