By way of illustration only, clause 14.11 of the 2017 Fidic terms provides as follows:

14.11 Final Statement: 

Submission by the Contractor of any Statement under the following provisions of this Sub-Clause shall not be delayed by reason of any referral under Sub-Clause 21.4 [obtaining DAAB’s Decision] or any arbitration under Sub-Clause 21.6 [ Arbitration] 

14.11.1 Draft Final Statement

Within 56 days after the issue of the Performance Certificate, the Contractor shall submit to the Engineer, a draft final statement.

This Statement shall:

a)     Be in the same form as Statements previously submitted under Sub-Clause 14.3 [Application for Interim Payment]; 

b)     Be submitted in one paper-original, one electronic copy and additional paper copies (if any) as stated in the Contract Data; and

c)     Show in detail, with supporting documents:

i)      The value of all work done in accordance with the Contract;

ii)    Any further sums which the Contractor considers to be due at the date of the issue of the Performance Certificate, under the Contract or otherwise; and

iii)   An estimate of any other amounts which the Contractor considers have or will become due after the issue of the Performance Certificate, under the Contract  or otherwise, including estimated amounts, by reference to the matters described in sub-paragraphs  (c) (i) to (iii) of Sub-Clause 14.10 [Statement at Completion]. These estimated amounts shall be shown separately (to those of sub-paragraphs (i) and (ii) above).

Except for any amount under sub-paragraph (iii) above, if the Engineer disagrees with or cannot verify any part of the draft final Statement, the Engineer shall promptly give a Notice to the Contractor. The Contractor shall then submit such further information as the Engineer may reasonably require within the time stated in this Notice, and shall make such changes in the draft as may be agreed between them.” 

Not only is delay the enemy, but in submitting the timely draft final statement to the Engineer, it has to include all matters relied upon by the contractor (and in detail) in support of the sums the contractor considers due to it from the Employer.

Scheduling can assist in identifying what is in dispute and why and to prioritise the largest items disputed and why.