At the end of the form it says to destroy the form after 2 years. Isn't it necessary to keep it in perpetuity if the roll book keeps their information in perpetuity ?

The form is likely to contain more personal data than the Roll book although it is recognised that the Roll Book may hold more personal data than just the name and date. Although the Roll book is a historical record that should be retained, where someone requests their name to be deleted from the Roll book, we would need to comply.  The Union is looking into the feasibility of providing a simple Roll book that is compliant with GDPR.