None of the three will play in either leg of the semi regardless. Assuming none of them advance (unlikely) Keita and Mane last play on the 18th and Salah on the 19th. They aren't going to fly back from Africa to the UK to play one/two days after their last match. So, not really seeing it?The benefit is that any delay gets them closer to the possible return of 3 key players from AFCON if their teams don't progress and/or get the League Cup semi final reduced to 1 game affecting their fixture congestion. It's not rocket science.