See clauses 61.1 and 61.3 for who should notify. In essence, if it is a compensation event under 60.1 (1) or (4), then the Contractor should notify and there is no time bar on the Subcontractor notifying. If under 60.1 (3), then the 7 week time bar of the ECSC will apply.
There is no difference under the contract in principle in how the CES are assessed. However, depending on the timing of the notifications relative to the event, the quotations may either be assessed as a forecast (event though the work may already have been done) or on records : see last para of clause 63.1.
Another factor to take into account is which 'event' will give you the maximum entitlement. I.e. the bigger the effect on Defined Cost, the greater you entitlement. Ditto for additional time under clause 63.3. This might affect which compensation event heading you notify the physical event under.
There is no difference under the contract in principle in how the CES are assessed. However, depending on the timing of the notifications relative to the event, the quotations may either be assessed as a forecast (event though the work may already have been done) or on records : see last para of clause 63.1.
Another factor to take into account is which 'event' will give you the maximum entitlement. I.e. the bigger the effect on Defined Cost, the greater you entitlement. Ditto for additional time under clause 63.3. This might affect which compensation event heading you notify the physical event under.