Hey dear,
Giving another shot of IELTS is always advisable if you're quite confident that you can boost your scores further. As many of us here, are uncertain like you, regarding when our files will be picked and believe me waiting really kills you. If you want to make better use of the time meanwhile sitting in the pool, then reappearing for the IELTS again would be helpful. That way you can make yourself busy and free from the anxiety for a while. 453/456 is a pretty good score, enough to witness an ITA. Go for it!!!