You are correct!

Since the bay went to "auto price index" operation(including higher fees) a few years back, I too have noticed odd early bids that drive certain auction prices up by X % .

Look at the times of the early bids (most of which never bid again).

Yes, you can set your bid for any time you like.

The bay claims "nothing odd about x auction" when I have opened cases.

Before the change, only "rare item" auctions had lots of early bid activity every so often.

Now it is just about EVERY auction!

It does not pass the smell test.

Trying to prove it is difficult.