Not "will", but might. This is biotech (not fantasy land, unfortunately). Before we do invest in a preventative trial, we will likely be testing the hypothesis with 2-73 in AD model mice. And they'll release the results. They don't keep them secret.
As for sleep effects, we have no support for a sleeping pill as you described. We do have initial support that 2-73 improves the sleep of patients whose sleep is impaired by certain CNS conditions. This is very different, so you have to be careful not to conflate them. This is also very different from alleviating symptoms of sleep deprivation, for which a study was done using an S1 agonist some years ago.