You could try 0901hrs - to 0859hrs, thus avoiding the 0900 reading, if your
software allows ?
I undertsand that certain professions for example dont have such a time at
0000hrs, they go for 2359 or 0001 to avoid problems
Paul Crabtree
Brampton N.E. Cumbria 117m ASL
Climatological Station 7076
http://www.bramptonweather.co.uk