MS Graph API truncating SingleValueExtendedProperties

When issuing queries to the graph API, if I target a specific individual object (e.g. an email) I can use $expand and return full values for SingleValueExtendedProperties, however, if I'm issuing a query (e.g. return all emails for the last three days) and using $expand to include the SingleValueExtendedProperties, the values of each SingleValueExtendedProperties are truncated.

I'd really like to not have to do an N+1 (return all objects then query them one-by-one) as I'm sure I'll hit a throttle at some point, but besides that would be terrible performance.

Anyone know why this would be the case? I cannot find any documentation that tell me this is normal behaviour or if there are query options to change/remove/disable the truncating limit.

I've been using these resources for documentation:

• https://docs.microsoft.com/en-us/graph/api/singlevaluelegacyextendedproperty-get?view=graph-rest-1.0&tabs=http
• https://docs.microsoft.com/en-us/office/dev/add-ins/outlook/metadata-for-an-outlook-add-in#get-custom-properties-using-ews-or-rest