Well done. The abbreviations can get confusing if two parties are not sharing the same map. Example, I give 204 as an Easting, but that could be 2204 or 3204 or 4204, etc...
One small technicality. The min and max eastings noted in the video only occur near the equator. As you go north or south the min and max eastings will narrow. For example up near 84 degrees north the min and max eastings go from 465,000 m.E. to 515,000 m.E.