ABM 30 Days provisional period

We are facing issues regarding the 30 days provisional period. Within the period user can leave MDM or Anyone having the device can remove MDM profile and enroll their own MDM , possibly. In that case It might be a bug. As a MDM vendor, We are asked to restrict this MDM removal from client within this provisional period. As far We checked, there is no proper solution for restrict the removal. We are in need to hold the devices for this provisional period, then release the devices to users. Please explain what is the need of 30days provisional period for ABM, if removed, it will be helpful.