Changing parameters of progressbar

I am using a Progressbar inside an advstringgrid.
It is programmatically added by this line
    AddProgressFormatted(1, rowidx, dwclCoral, clBlack, clInfoBk, clBlue, '%d', 0, 600);
This works fine, but depending on other parameters I should change the range of the progressbar on the fly.
For example, the value 600 should change.
How can I do this ?
Readd the progressbar ?
Delete it and add it again ?
Or is there a better way ?