Thank you for contacting our technical support! My apologies for the delayed response here.
Since these labels are generated by Parcelforce we cannot amend the date. However, you can set the correct Pickup Schedule in Parcelforce integration (Shipping > Integrations > Parcelforce > Config), that way the label will show the correct date. Let's say your pickup is 4 pm, then any label printed after this time will have next date printed on the label.
In regards to the email that is sent after printing the label, I am afraid we do not have control over it as it's triggered by Parcelforce.
I hope this helps! Please, let us know if you requrie further assistance.
Have a nice day ahead!