Abstract: This is the second of two talks on time-frequency methods for GKP-codes. Building on the framework developed in the first talk, we focus on the stable representation of codewords and the analysis of displacement errors. We present a stable coefficient theorem for ideal GKP-codewords, explaining how a finite family of time-frequency coefficients determines the logical state and how the choice of probe enters the reconstruction and its stability. The Zak transform provides a common perspective on these coefficients and the error syndrome, which we use to discuss syndrome estimation. We then consider regular approximations of ideal codewords and the resulting approximation and error estimates. Time permitting, we will outline an extension to mixed states using quantum time-frequency analysis.This is based on joint work with Franz Luef (NTNU Trondheim), who gives the first talk.