While I don't promote pool jumping,  this is  false logic.  The PPLNS charge-up/wind-down time are symmetrical.  You do not lose anything by mining on a PPLNS pool for a few minutes, nor do you lose anything by leaving it after a few hours.  It is unhoppable because it uses a backward-looking payment allocation, not because it penalizes you if you don't mine constantly.  The expected payout per share on a PPLNS pool never changes based on timing/frequency of submissions.  Every share submission has the same expected payout whether you quit mining immediately after sending it, or if it was your first submission.