Fermi Paradox and SETI statistics: are best candidate signals actually from ETI?

A possible answer to the Fermi Paradox is that SETI efforts have, in fact,
intercepted radio transmissions from extraterrestrial civilizations, among
the “strong candidate” signals:

Suppose that, in our galaxy, there are, in fact,
numerous sites with a high-tech presence,
that are in active contact with other such places,
but such places do not include Earth.
The senders would know in which direction to send their signals,
but said directions must continuously vary, because everything in our galaxy moves,
mostly in closed orbits. Suppose we have, many times over, intercepted such a signal,
when Earth happens to be in the way, but then we lose the alignment
and can’t pick up the signal again.

At this point, I imagine that we must have cataloged enough candidate signals
that one could attempt a statistical analysis of observed fade-in, fade-out,
and compare that, to what a model would predict, based on our general knowledge
of the motion of stars in our galaxy.

Question:  Has such a study ever been attempted?