Here both are the different

Accelerated stability

testing only 40°C/75 RH

Study here  time period are 1,3,6,12

Each batch perform Accelerated stability study

Here we have to seen that naturally degraded drug product which is covered  According to WHO guidelines

storage condition of climatic zone IVa and zone IVb? Zone IV a: 30°C and 65% RH (hot and humid countries) Zone IV b: 30°C and 75% RH (hot and very humid countries Countries(e.g., 50°C, 60°C) comes under climatic zone IVb? Brazil, Cuba, China, Brunei, Cambodia, Indonesia, Malaysia, Myanmar, Philippines.

 Force degradation

oxidation, and photolysis, hydrolysis, alklalation, high humidity, temperature etc test perform,

Required only one batch during DMF file submition.

Purpose force degradation

identify the likely degradation products, which can in turn help establish the degradation pathways and the intrinsic stability of the molecule and validate the stability indicating power of the analytical procedures used.