We've encountered an issue where the event funnel is constructed incorrectly due to a large delay between server_received_time and client_upload_time.

According to the documentation, when the difference is more than 60 seconds, a correction is made using the formula: event_time = client_event_time + (server_received_time - client_upload_time) Link: https://help.amplitude.com/hc/en-us/articles/229313067-Look-up-event-data-for-individual-users

For some of our users at the start, this delay is present, and then it disappears, which causes initial events to land in the middle of the stream. For instance:

The issue is that such users end up dropping out, making the starting funnel incorrect.

All our products are based on Unity and use the Amplitude plugin 2.7 for Unity.

How should we address this issue? Is there a way to force the calculation of event_time = client_event_time?

In your case, it's best to either fully rely on server time or client time, but not to make intermediate calculations.