Well done to those that are saying no. And you're all correct about crewing not remembering when you helped them out. Most of us are pushing 90 odd hours per month, are tired (if not fatigued) and now they want you to voluntarily expose yourself (fnarr) to more potential errors by flying in this state, only to be hauled over the coals, demoted to FO or sacked if you make a mistake. Guys, look after yourselves and Families and politely say no.