The 2048 blocks still have to be solved at high difficulty before a readjustment, regardless of how many miners turn off their rigs. If enough miners shut down due to lack of fiat income, the readjustment could go from weeks to months to years as the block times get longer and longer (and confirmation times also get VERY long, essentially killing the coin).
If this change in price happens very fast, maybe miners don't notice it before the next difficulty change.
Miners turn of their equipment but there are only a few blocks left till difficulty change.
This is also a possible senario.