I'm using google captcha on my forms. Spam is automatically generated by the robot. The Date field contains a letter in the sent message. By default, you can not send a form when the letter is in the Date field.
They probably use some backdoor, you do not have to use captcha to send.
Do you have any information where the problem is?
I also noticed that the most goes into 2-10 hours after the update.
Please post a screenshot of your settings for the form On Submit event.
ChronoForms technical support
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