There is a reference in the LPP 2.0 discussion thread that talks about “History Sensor Data” (see below). The author of the thread (appears to be a myDevice’s guy) suggests that all of the data types disclosed are supported in the LPP spec but that the official docs have not been updated.
Does the App Server support this type of data format with the delta timestamp?
4.4. History Sensor Data
When sending history data, the data channel is identified with the Frame Port. The device must send data on the Frame Port equals to the data channel added to 100.
Frame Port = Data Channel + 100
First byte of the Payload must be the Data Type, then each data is prefixed with the time elapsed between the measurement and the frame TX, expressed in seconds with a 2 bytes integer.