The cloudflare messages will continue to appear until the attack subsides. The holding page is making a technical assessment that your request is genuine. If this wasn't done the site would typically be on its knees and unresponsive.
Without knowing the details this is most likely an attempt at blackmail. Assuming its blackmail, the attackers are waiting to see if the site owners pay the bitcoins (or other cryptocurrency) to stop the attack. At some point the budget the attackers have to fund the attack (they typically rent attack resource also paid in bitcoins) will run out, and everyone moves on. If you're really lucky law enforcement might get an angle on the perpetrators of the attack, but that's fairly rare.
Having seen the consequences of denial of service attacks elsewhere, FlyerTalk are at a technical level well prepared and have the right defenses in place, and although the holding page and database errors are inconvenient, they are doing the right thing so bear with them. At the current time the only thong iithink they could to do to improve might be a sticky announcement might help spread the word that they are busy working on the issue.