I was using 5.11 with no issues until last week.
Last weekend, I updated 2 of my macs with last Catalina security update, a rMBP 15" 2013 and a Touch bar MBP 16" 2019.
Today, both have the Kernel Task full throttle issue, with 5.11.
With 5.6.1 no issue.
Other mac, a Mac pro 5.1 six core xeon 2012, don’t have the problem, but it is not updated to the last Catalina security upgrade.