Tweets from scheduled posts

I don’t know if this is a feature of PRO only. But when I create a post and publish it immediately the tweet is sent. If I create the post and then use WP to schedule it to be posted say the following day, the post appears within WP at that time, but the tweet doesn’t get sent. Is that something that only happens if I upgrade to the PRO version?

http://www.ians-studio.co.uk
@ianbutty

https://ww.wp.xz.cn/plugins/wp-to-twitter/