Actually i might have a better idea. Beach Station can be the
splitting point for Route 61.
Route 61: EUN-Beach Station (operated by Serangoon
contractor)
Route 991 (new): BBT-Beach Station (operated by Chua Chu Kang
contractor)
Eunos -- Sentosa maybe still okay. Or, if Beach Station ends up
to be too crowded, Eunos -- Harbourfront is a decent
alternative.
Bt Batok -- Sentosa cannot due to the loss of direct links
between Commonwealth and Chinatown/Bugis. That end is better off to
terminate at Marina Ctr or Lor 1 Geylang.