Provided further, that in all cases whatsoever where an augmentation or modification of stipend shall have been or shall be applied for, and which shall be judged of, or a decision pronounced therein, after the passing of this Act, by the said lords of council and session as commissioners aforesaid, it shall and may be competent to them to refuse to augment or modify any stipend in any such case, either on account of there being no legal fund of augmentation or on account of the circumstances of the case; and it shall and may be competent for any party or parties to propone all relevant objections in every case whatsoever where an augmentation or modification shall be applied for, and which objections shall be determined by the said lords of council and session as commissioners aforesaid as heretofore.