It was was thought that the London Stadium Security Advisory Group (SAG) which includes the Metropolitan Police would look to drastically reduce the away allocation on safety grounds but that has not been the case.
There has been clashes with away fans during the Watford premier league game due to poor segregation within the stadium as well further clashes outside the stadium at the Bournemouth and Middlesborough Premier league games.
One suggestion is to keep away fans behind a period of time to allow the majority of home fans to disperse but the police are known not to favor this tactic. The evening Chelsea game has the extra complication of being a London derby and a evening game with possible extra time and penalties meaning keeping Chelsea fans behind could be impractical.
On Saturday some West Ham home fans had their exit blocked by stewards and police to allow Middlesborough away fans to leave causing extra frustration.
The game is likely to rated to a category C+ high risk with a heavy police presence both inside and outside the stadium. Stadium owners are expected to have a temporary radio in place by then to solve a small number of reception black spots.