lower incubation temptures on day 26?

[JHducks3]

hi
ive got 4 more days until my ducks hatch

they are at a tempture of 37.7C as advised by my duck book but it advises to decrease the tempture from day 26-28 to only 37C
should i do this?

any advise?
thanks guys

 

[mnferalkitty]

I hatch LOTS of ducks and have never lowered temps