船东能否撤销新的laycan？

41号跑鞋

杨老师，请教一个问题：
油轮租船合同有如下的CANCELLATION CLAUSE:
  IF IT BECOMES OBVIOUS TO THE OWNERS THAT THE VESSEL WILL NOT
  MEET HER CANCELLING DATE, OWNERS NOTIFY CHARTERERS OF VESSEL'S
  ETA AND PROPOSED NEW CANCELLING DATE.
  CHARTERERS HAVE THE OPTION TO CANCEL THE CHARTER WITHIN
  48HOURS, EXCLUDING SATURDAY, SUNDAY AND HOLIDAYS, OF NOTICE
  OR EXTEND IN ACCORDANCE WITH OWNERS NEW PROPOSED CANCELLING
  DATE. IF CHARTERERS DECIDE CANCEL THE CHARTER, IT SHALL BE
  WITHOUT ANY FURTHER LIABILITIES TO EITHER PARTY.
  IF CHARTERERS DO NOT CANCEL THE CHARTER WITHIN 48HOURS,
  EXCLUDING SATURDAY, SUNDAY AND HOLIDAYS, OF RECEIPT OF OWNERS
  NOTICE, CHARTER PARTY IS MAINTAINED ON BASIS OF NEW CANCELLING
  DATE PROPOSED BY OWNERS.

如果船东宣布了miss laycan,同时提出了新laycan，在租家宣布是否取消此合同之前，船东是否有权利撤销所提出的新laycan，从而使合同继续维持？（合同里规定租家有权在48小时之内决定是否取消合同）。合同适用英国法，法律依据何在？非常感谢您的答复！