The FAQ entry on CW reads:
The original author keeps the reputation gained (or lost) before their post entered community mode.
However, I just discovered that converting a post to CW within the 5 minute grace period removes any reputation already gained from upvotes. This is, at the very least, undocumented behavior.
IMO, converting to CW within the grace period should count as separate entry in the post's revision history, in much the same way as edits by other users do. Additionally, regarding reputation:
- Either the FAQ should be updated to reflect that CW during the grace period is an exception to the above mentioned rule, or
- The behavior should be altered, so that reputation from upvotes prior to CW are retained regardless of whether the change occurs during or after the grace period
I believe the second option is much more intuitive and would cause less confusion in the future.