The expert may, on proof of the progress of his operations, be authorised to deduct an advance from the sum deposited if the complexity of the case so requires.
In the event of a manifest insufficiency of the advance allocated, in the light of the work done or to be done, the expert shall report this without delay to the judge, who, if necessary, shall order the deposit of an additional advance to be borne by the party he determines. If no deposit is made within the time limit and in the manner set by the judge, and unless this time limit is extended, the expert will file his report as it stands.