Which means that they either need to make sure they write an entry, convince someone to give them a "gift bye", join a team that shares byes, or tag someone else into the game to take their spot.
I've decided to keep doing this as a helpful "poke" to the people on the edge. Most of them probably remember. But just in case they don't... also as a way of outlining their options. (other than just dropping)
Of course, another reason is that I know few people can resist the "why isn't so and so on the list?" which will help me keep my spreadsheet up to date. ;)