Additional API points to note

Query String Length: The maximum length of the query string is 2048 bytes.
The error message response is nvarchar(100).
A REST API call to the Hub accepts a single entity per call. For example, the client must make a new <request> call to the hub for every sales order.
Push message entities are sent in parts. Multiple entities can be sent at once. In an example for Push Stock Adjustment, each separate adjustment entity/part will be sent wrapped in "Responses" and "Response" tags.
The maximum character length of the URL endpoint is 300
For Push JSON, Null or "" is returned when there is no data, i.e., "SalesInvoiceNumber": null, or "DeliveryAddressLine2": "",. Empty entities can be changed to {} if required.
For Push XML, an empty entity is returned, i.e. <DeliveryAddressCounty/>
The endpoint and API is different between the UAT environment and Live within a client entity
DC data is separated
The message parts are sent one after the other. MessagePart 1 then MessagePart 2 then MessagePart 3 etc.

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