Extension published - March 31, 2019. Thank you to whomever got around to this.
Be sure to take note that this is only for national endorsements, not STCW.
It’s useless for anyone sailing vessels greater than 200 GRT / 500 GT outside inland waters.
Although with the track record I’ve seen of companies not realizing when STCW applies (“we’re not going international so person X doesn’t need a valid STCW medical”, “person Y doesn’t need II/2 unless we go foreign”, etc) I expect the only people that will be restricted from sailing are those going foreign.