Hi there,
Thanks for contacting us! We’re happy to support you.
We assume that it might be caused due to a delay in CRON triggered.
The Email Subscribers lite emails are sent using Hosting email sending & Host CRON..
Cron triggers emails sending at regular intervals every 15 minutes, it will run four times within an hour. So, you can set around 60 * 4 = 240 emails that can be sent per hour. Could you please check with your hosting about your email sending limit per hour? and update that into the Email Subscribers > Setting > Email Sending.
Whereas, another reason can be regular traffic on site, which triggers WordPress cron, and that cron triggers email sending and ensures timely delivery. If there isn’t sufficient traffic on the site then the admin will need to set up an external cron service for timely delivery.
Here is our doc which can be helpful in this regard.
Regarding your concern about the “message in the backend”.
This message refers to the automatic CRON hitting feature you experienced in the first 14 days of installing our plugin. Email Subscribers automatically hit the CRON on your site, resulting in timely delivery of emails.
Hence, as you’re using the lite version now email sending depends on your host sending limit and site traffic.
Let me know if you have any other confusion or questions.
Happy to support!.