^ Information about BOWP is here - http://www.cic.gc.ca/english/resources/tools/temp/work/prov/bridging.asp. This supersedes OB485a (and is currently exactly the same).
If I understand correctly, your friend wants to reapply for CEC.
Whether she will have to "leave Canada" altogether depends on her ability to remain as a visitor, but she won't be able to work unless she applies for a new work permit.
If she intends to use the AOR from her second CEC application to get a second BOWP, this part of the BOWP instructions applies (emphasis added):
"Where it is clear that complex or contentious issues/concerns exist on the application for PR, the WP application should be referred to a local office for additional review. Once satisfied that any complex/contentious issues have been resolved, the local office can issue the WP [...]
The WP is to be valid for the duration of one year from the date of issuance. Subsequent requests from applicants to extend their stay on an open WP will be considered on a case-by-case basis."