Whenever the financial statements required pursuant to subdivisions (a), (b) or (c) of Section 1384 are to be reported upon or certified by an accountant other than the accountant certifying the plan's most recent filing, the plan must furnish the Director with a separate letter stating whether in the eighteen (18) months preceding the engagement of the new accountants there was any disagreement with the former accountants on any matter of accounting principles or practices, financial statement disclosure or auditing procedures, which such disagreement if not resolved to the satisfaction of the former accountants would have caused him to make reference to the subject matter of such disagreement in his opinion or report. This letter must be verified by a principal officer of the plan. The plan shall also request the former accountants to furnish them with a letter addressed to the Director stating whether he agrees with the statements contained in the letter of the plan and, if not, stating the respects in which he does not agree. The notification by the plan along with the former accountant's letter, if necessary, must be furnished to the Director within 45 days of the engagement of the new accountants.