Omicron variant is aware of the vaccines. It is mutating precisely in the heptad repeat region where the protein must be stabilized before proceeding with vaccine development. The pre-fusion form of the protein must be stabilized first. Omicron N969K is that mutation. The commie virus has a modus operandum. It is by manipulating branched-chain amino acids either by varying among the three branched-chain aminos (leucine, isoleucine, valine, L, I, V, respectively), or by creating multiples of these when it mutates.
Chinese ferret badger coronavirus spike at position 969 is isoleucine.