https://www.charltonafc.com/news/addicks-face-welling-behind-closed-doors-friendly Charlton’s U23s were originally due to face Welling United at Park View Road. This fixture has been postponed and replaced with the behind-closed-doors fixture for the first team. This from the CAFC website article. That explains why it's behind closed doors, short notice change so no time to arrange tickets presumably. I wonder why the original U23 game had to be postponed.