2000 E240 engine oil overfilled

[usaustria]

Independent mechanic overfilled my E 240 by about 1/4 inch as measured on dip stick. Computer tells me to reduce oil level. Does that need immediate attention or can I wait until I have time to do it? What problems coud arise by that kind of overfill. I already drove about 400 mls since oilchange(overfill)
Thx,
Reinhard