This is why the transcript is going to be released (odds are it will be modified), so that they can try to win the war in the press before impeachment hearings get started. Once the hearings start, blocking them will not work, the courts have shown they will step aside in the case of impeachment and force the administration to turn over documents. If the administration continues to block in the face of that, they will soon appear to be guilty with the public, and information will come out through the press instead, as some people will leak if they think they have a chance to take Trump out.
Everyone has been piling on Pelosi, but she had to play this smart and wait for a real push for the impeachment process to start…this event has apparently infuriated the Democrats enough that they are getting behind it, even in purple districts, and people who understand are pretty much furious over such blatant corruption. We’re going to be in constitutional crisis mode for a while now, the Republicans will block everything and try to defend Trump to the fullest…remember that when the truth is finally revealed, they need to be held to account for enabling all of this.