text: but i see at a higher and lower zoomlevel on opentopo that this way does appear, at least in part, so it may well be that opentopo has old tiles at certain zoomlevels that need to be refreshed, which i trust will happen eventually, as i don't know how frequently they get updated (days, weeks, months).
  
  the data appears fine so i'd say be patient if it's still a problem without cached tiles, or point the stale tiles out to opentopomap.
  
  marking as resolved for this reason; if the link you gave is useful for later checking, feel free to re-open this