IPS - no mention about adverse market events?

Isn’t it prudent to include in the IPS what to do in case of adverse market events?

There’s a mention of ‘reviewing’ the IPS when CME changes but isn’t that like a long hard process to start doing under stressful conditions?

When the CME is formulated, they will have done simulations/stress tests on the potential results (in terms of investment objectives and risk tolerance) when there are changes in CME.