Gmail with >10 recipients is refused Mailtrap SMTP connections

A single email sent from Gmail with more than 10 recipients spawns more than 10 SMTP connections to Mailtrap, resulting in errors.

535 5.7.8 Too many connections per account

Mailtrap limits the number of concurrent SMTP connections per account to 10. https://help.mailtrap.io/article/100-sending-limits

Gmail breaks an email to 20 recipients into 20 emails to a single recipient and creates an SMTP connection for each of those emails.

I am using Gmail in a web browser with "Send mail as" configured to send an email from my domain via live.smtp.mailtrap.io. I first noticed the issue using https://www.mailreach.co/email-spam-test (30 recipients), but it's easy to replicate by sending any test email with 11 or more recipients.

This is really a Gmail problem: their use of SMTP connections is horrible. However, Mailtrap might want to consider something to accommodate it.

Also, there's no indication on Maitrap's Stats page that SMTP connections were refused, it gives the impression that everything is fine.