Time-resolved small-angle X-ray scattering (SAXS) was used to examine the kinetics of the transition from hexagonal (hex) cylinders to body-centered cubic (bee) spheres at various temperatures in poly(styrene-b-ethylene-co-butylene-b-styrene) (SEBS) in mineral oil, a selective solvent for the middle ethylene-co-butylene (EB) block. Temperature-ramp SAXS and rheology measurements show the hex to bcc order-order transition (OOT) at similar to 127 degrees C and order-disorder transition (ODT) at similar to 180 degrees C. We also observed the metastability limit of hex in bee with a spinodal temperature, T-s similar to 150 degrees C. The OOT exhibits three stages and occurs via a nucleation and growth mechanism when the final temperature T-f < T-s,. Spinodal decomposition in a continuous ordering system was seen when T-s < T-f < T-ODT. We observed that hex cylinders transform to disordered spheres via a transient bee state. We develop a geometrical model of coupled anisotropic fluctuations and calculate the scattering which shows very good agreement with the SAXS data. The splitting of the primary peak into two peaks when the cylinder spacing and modulation wavelength are incommensurate predicted by the model is confirmed by analysis of the SAXS data.