Reference

.htaccess

Execute redirect after specified date/time

RewriteCond %{TIME_YEAR}%{TIME_MON}%{TIME_DAY}%{TIME_HOUR}%{TIME_MIN} > 201804240000
RewriteRule ^path-to-be-redirected$ /redirect-path [R=301,L]

Redirect both www to non-www and http to https

RewriteEngine on

# Redirect www to non-www
RewriteCond %{HTTP_HOST} ^www\.(.*)$ [NC]
RewriteRule ^(.*)$ https://%1/$1 [R=301,L]

# Redirect http to https
RewriteCond %{ENV:HTTPS} !on
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]