Here is another thread on this matter in Racing Category.
In particular the evidence collected already on this . It looks pretty damning and completely undermines any credibility in Zwift racing as it currently performs . The proof positive provided here (and seems to be expected ) is that two users will see competely different versions of a race and there is no quality or resilience on this at all . In a case shown the person who crossed the line first ( by a decent margin) was actually 2nd 
There is no “game” that can expect to be taken seriously in a Multi-player competitive aspect that cannot guatantee some degree of consistency here . Take any MMO shoot em up where the players you were targetting were not even there , quite rightly no one would play that game . This is the same here .
This has without doubt increased as an issue in the last few weeks . But lets be clear is this just pushing an already flawed approach (which would need a complete rethink ) to multi user interaction or has it been introduced and can be bug fixed .
We would like some answers on this please @ZwiftHQ .
Silence on this can only suggest to me the former is the case . Tell us we are wrong .