Emanuel,
"Days to full" calculation uses the trend line that is shown in Ops
Manager capacity graphs. The trend line is calculated by performing a
linear regression of upto 90 days data.
Daily growth rate of the volume is the based on slope of trend line,
days to full is (total space - used space)/(daily growth rate).
If the volume size changes, the days to full will be adjusted accordingly.
Thanks,
Raj.