billyonthemountain
The speedlimit on this section of the secondary road is normally 50, with sometimes a digital sign board displaying a maxspeed of 30km/h. The schedule should be surveyed in order to complete the maxspeed:conditional tag. 

See discussion in https://www.openstreetmap.org/changeset/104206857

The same applies to Paul Hymanslaan further west (same changeset).

It is assumed that the schedule is related to the nearby schools.