$ While in the "do the job case" you liquidate the portfolio at $t_1$ realising its PnL (allow me to simplify the notation a little bit) Stack Exchange network is made of 183 Q&A communities which includes Stack Overflow, the most important, most reliable on line Local community for developers https://elliottwzkps.alltdesign.com/examine-this-report-on-pnl-53274719