[OSM-talk] Some tiles not rendering?

[Nakor]

   Hello,

It looks like some tiles are not rendering. For instance 
http://b.tile.openstreetmap.org/17/35226/48373.png/status has been "due 
to be rendered" for the last 24 hours when 
http://b.tile.openstreetmap.org/15/8816/12104.png/status has been 
updated today.

Why would some tile render and some not?

   Thanks,

N.