> We should receive a BackOffMilliseconds field in the response according to https://learn.microsoft.com/en-us/exchange/client-developer/exchange-web-services/ews-throttling-in-exchange, but it's unclear whether this is always present
No, it won't ;-)
Bug 1892085 Comment 3 Edit History
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> We should receive a BackOffMilliseconds field in the response according to https://learn.microsoft.com/en-us/exchange/client-developer/exchange-web-services/ews-throttling-in-exchange, but it's unclear whether this is always present
No, it won't always be there ;-)
This is Exchange...