I just found a cool new feature on OWA – and best this is available on both Exchange Online and Exchange 2016 On Premises.

When you use OWA to setup a meeting request, you have the option to configure a message reminder (not the ‘classic’ pop up reminding you your meeting in 15 minutes)

The option to configure the mail reminder is available just below the ‘classic’ reminder option

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When you configure this option, you have the choice to send the reminder to you or everybody as well as when you will receive it

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Once you have configured it you can add, edit or delete the reminder at any time; even after sending the invitation.

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And this is the message you are getting

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