Dear Devanand,
The one-month notice mentioned in Section 25-F is one of the conditions precedent to the retrenchment of workmen in general. The three months' notice under Section 25-N is one of the conditions precedent to the retrenchment of workmen employed in any industrial establishment to which Chapter V-B of the Industrial Disputes Act, 1947 is applicable, i.e., which has a strength of not less than 100 on average during the preceding 12 months.