We are currently at month 32 of a 19 month contract (we expect to complete month 34), our package has been increased significantly over this period and we are still receiving changes to Works Information, what are we entitled too prolongation wise?
Your contract data part 1 will have stated the Completion Date (month 19) and also the interval in which you have to submit revised programmes for acceptance (typically every four weeks or every month). Your first programme either referenced in data part 2 or submitted/accepted after contract award should have shown a planned Completion on or before the Completion Date (month 19).
Then as you moved through the project, each instruction issued changing the Works Information should have been notified as a compensation event, and then quoted and assessed/implemented by the Client. Each compensation event that affects the remaining works you are obliged to submit a programme as part of the quotation demonstrating the effect on your planned Completion - which then once implemented would allow Completion Date to move by the same amount.
Each compensation event the other Party can prompt the other to move it along, but unfortunately under NEC2 you do not have the deemed acceptance loop introduced with NEC3 where by if they do not respond to your Contractor quotation then you notify them, and two weeks of further no response means it is deemed accepted.
Every four weeks/month you should have been updating your programme and showing where planned Completion was as a result of progress and all the compensation event to that point. If planned Completion was moving any month - you should have been able to equate what that was down to i.e. Contractor delay or due to a compensation event. If the latter - you should then make sure you have that CE in the system i.e. notified and then quoted for.
There is no such thing as a “global extension of time” claim under NEC. The only way to get Completion Date moved is through the assessment of compensation events which both Parties should be managing during the life of the project. It sounds from your question like some or all of these processes described have not been followed and if so you have no choice but to go back and try to prove/justify this retrospectively which is very subjective and time consuming.
Very unusual to still hear of anyone working under NEC2 given NEC3 came out in 2005 and now we have NEC4!