This was achieved by 

blocking prior and future financial periods in Sage through Maintenance….Common… company details…..accounting periods screen. You can also block change transaction processed date option so that users cannot change transaction date when processing. Depending with your software version look for the option below under agent administration user permissions. Adjust the setting to the POS user group or individual user accounts.

This was achieved by 

blocking prior and future financial periods in Sage through Maintenance….Common… company details…..accounting periods screen. You can also block change transaction processed date option so that users cannot change transaction date when processing. Depending with your software version look for the option below under agent administration user permissions. Adjust the setting to the POS user group or individual user accounts.

Yip, I fully agree

I didn't thought of the Retail permission you mentioned to prevent users from changing the transaction date - glad you figured it out!

Kind Regards

Bennie