Have central banks made this switch before?

Not often. The BOJ let its balance sheet shrink in 2006-07, 

in what many regard in hindsight as a premature tightening of policy amid Japan’s continuing battle with deflationary pressures. 

The European Central Bank also allowed its asset holdings to drop in 2013-14 following a surge during the euro crisis. 

The Fed used QE for the first time in the midst of the 2008 financial meltdown and during the weak recovery that followed, 

then implemented QT once it thought the economy was sufficiently strong. 

The tightening lasted for a little less than two years, from 2017 to 2019.

https://www.bloomberg.com/news/articles/2022-01-05/for-fed-taper-rates-then-quantitative-tightening-quicktake

그렇다고 한다