Hi, maybe this can help you, I follow these steps to change local time, in this case to 'Europe/Madrid':
uci set system.system.timezone='CET-1CEST,M3.5.0,M10.5.0/3'
uci set system.system.zoneName='Europe/Madrid'
uci commit system
/etc/init.d/system restart
uci show system
And to perform a subtle adjust:
date -s 2022.04.21-10:46 using this format: [YYYY.]MM.DD-hh:mm[:ss]
BR
MC