Excel Protected Workbook Known PW Length

[secpro]

p.s. I accidentally cancelled the JtR session after a fruitless 16 hours and now I'm back at square 1.

Try adding --restore to the command line and it might pick up where it left off.

Given a rate of 291/s, trying all uppercase and lowercase letters should take about 7 hours, if I'm doing the math right.
Note that hashcat will not make it super obvious when it's found; there won't be a popup or anything.
You'll be watching the 0/1 line and see when it changes to 1/1.