NEC3 ECC: Ambiguity within "Preambles"

we have a Preambles in which the schedule of rates have been deemed to have taken into account,

within the document there is the General Preambles, which states;

PG.5 The rates and prices inserted in the Schedule of Rates are to be the full inclusive value of the work described, including all costs and expenses which may be required in and for the construction of the work described, together with all general risks, liabilities and obligations set forth or implied in the documents on which the tender is to be based

further in the document the preambles state;
The item descriptions in the Schedule of Rates for Class E items have been prepared in accordance with the following preamble clauses

within series E there is no mention of multiple handling of materials, which the client states is covered in PG.5,

As the rate falls under Series E and they are said to be based on the following preambles, does this cause ambiguity

It is difficult to give an answer to this question without site of the documents to which you are referring.

One thing that springs to mind is why are you having to handle the materials multiple times? Is it an additional constraint being imposed on you by the Employer / PM? If so then you may be entitled to a compensation event.

If there is an ambiguity or inconsistency you should notify the PM under clause 17.1, then depending on how the PM resolves it you may be entitled to a compensation event.