staff endpoint suddenly not working

We call the https://api.servicem8.com/api_1.0/staff.json endpoint for our environment. As of last night we have started getting a CloudFront error on call.

If we filter based on edit date and slowly increase the filter, we can manage to get a call to succeed and return 203 staff, but any higher than that, the call fails.

Anyone know whats going on? Seems like something changed yesterday as we make this call multiple times a day and it was working last week.