The fact that she is on Homecoming that's how they seem to go.
Just like if they did ads of Rebecca or Meav for the Destiny Tour.
People would say where is Meav at for the tour or who left the group is it Susan or Mairead because new girls or members falls when someone departs. It wouldn't be as bad if they used anything Alex Sharpe considering they know she was on this tour not knowing when Susan is back on and not her.