curl -w times shown as microseconds instead of seconds with fractions

[notsure2]

root@linux:/opt/root/bin# /opt/bin/curl --version && /opt/bin/curl -w '%{time_total}\n' -o /dev/null -s 'http://www.cnn.com/'
curl 7.72.0 (arm-openwrt-linux-gnu) libcurl/7.72.0 OpenSSL/1.1.1h zlib/1.2.11
Release-Date: 2020-08-19
Protocols: file ftp ftps http https imap imaps pop3 pop3s rtsp smtp smtps tftp
Features: HTTPS-proxy IPv6 Largefile libz SSL
0.236153

root@linux:/opt/root/bin# /usr/sbin/curl --version && /usr/sbin/curl -w '%{time_total}\n' -o /dev/null -s 'http://www.cnn.com/'
curl 7.74.0 (arm-unknown-linux-gnu) libcurl/7.74.0 OpenSSL/1.1.1i zlib/1.2.11
Release-Date: 2020-12-09
Protocols: file ftp ftps http https imap imaps mqtt pop3 pop3s rtsp smb smbs smtp smtps tftp
Features: alt-svc HTTPS-proxy IPv6 Largefile libz NTLM NTLM_WB SSL TLS-SRP UnixSockets
126886

Is this documented anywhere ? This is a MAJOR breaking change in a minor release.