(a)Should the Vessel not beready to load (whether in berth or not) on the agreed cancellingdate, the Charterers shall have the option of cancelling thisCharter Party.
(b)Should the Ownersanticipate that, despite theexercise of due diligence, the Vessel will not be ready to load bythe cancelling date, they shall notify the Charterers thereof withoutdelay stating the expected date of the Vessel’s readiness to loadand asking whether the Charterers will exercise their option ofcancelling the Charter Party, or agree to a new cancellingdate.
Such option must be declared by the Charterers within 48 runninghours after the receipt of the Owners’ notice. Ifthe Charterers do not exercise their option of cancelling, thenthis Charter Party shall be deemed to be amended such that theseventh day after the new readiness date stated in the Owners’notification to the Charterers shall be the new cancellingdate.
The provisions of sub-clause(b) of this Clause shall operate only once, and in case of theVessel’s further delay, the Charterers shall have the option ofcancelling the Charter Party as per sub-clause (a) of thisClause.
source: https://www.bimco.org/en/Chartering/BIMCOClauses/Cancelling[]_Clause_2002.aspx