It is in their rule book. They definitely let both parties know before. That is not debatable at all.
How far in advance, that is.
In their procedure, they say the three judges recommend the outcome, the president decides it. And then it states that they notify both parties. So, if you wanted to, which i do, you Could read into that that both parties know as soon as the president signs the decision. Which, again, i want to, would coincide with CAS releaskng the date the decision will be made public. Which, happens to coincide with a burst of bravado reported around the club, by pep and behind the scenes.
That of course is pure speculation (fucking contagious this positivity optimism malarkey isnt it). But the fact that they let both party know in advance is in fact, de facto and ipso facto, a fact.