Inflation Rates at different points in a business cycle (Peak vs Expansion)

Hello all,

In the schweser material it states that “inflation rates MAY increase” during expansion and that “inflation rates increase” during a peak.

I would think the opposite… during an expansion you almost definitely would have inflation rates increaseand during the peak you make have inflation rates increase?

For the contraction it says inflation rates decrease with a lag (makes sense) and that during a trough, there is amoderate or decreasing inflation rate.

Could anyone explain the reasoning behind the inflation rates at different points in the cycle? Especially during the peak and expansion.

Appreciate the help!

Anyone?