Odd conflict in data charted this morning

["Owen Davies" <owen@xxxxxxxxxxxxx>]

No doubt everyone else already knows all about this,
but since I don't ...

I was watching September T-bonds this morning,
with charts of several bar lengths, from 1 minute out
to daily, when I noticed a conflict between the
corresponding bars on different charts.  The 1-minute
bars just efore 9:00, and then again at 9:12, showed
highs of 100-10.  However, the 15-minute bar showed
highs of 100-10 before 9:00 and only 100-9 on the bar
from 9:05 to 9:20.  The 15-minute chart eventually fixed
itself, but not until well after the 9:35 bar had begun to
form.  It's not a serious problem for me, but it has me
curious.  Does anyone know why this happens or how
to correct it?

Thanks.

Owen Davies