Membership 2 Pro -- no longer sending emails since update

After I updated Membership 2 Pro last week, the plugin has no longer been sending emails. This was never a problem before, so I'm not sure what to make of it. Is this a known bug? It seems like maybe a plugin conflict, but the only change we made was updating Membership 2 Pro, we did not add any plugins.

For reference, we use SendGrid to handle outgoing mail for the site, which overrides the default WP Mail functions. This has not changed, and eNewsletter and other WPMUdev plugins are still working and sending mail normally.

The site is live with members using it daily, so it's tough to check for plugin conflicts by deactivating them without breaking the site and potentially running off clients. I granted support access.

Any insight you could provide would be super helpful! Thanks!