Forward Emails while Out of Office
Set up Email Forwarding
Has to be set by the user or someone with access to their email but can be done in advance.

Go to File menu then click Automatic Replies (Out of Office)
Click on Send automatic replies
Set the start date and time
Set the end date and time
Set an appropriate message (according to company rules)
Click on the Outside My Organisation
Set an appropriate message (according to company rules)
Tick Auto-reply to people outside my organization.
Click on Rules… at the bottom left

Untick Show rules for all profiles
Click on Add Rule…

Tick the Sent directly to me and Copied (Cc) to me boxes
Tick Do not process subsequent rules box
Tick Delete box
Tick Forward box
Keep Method: as Standard
Click To…

Search the name you want the email forwarded to.
Click on the name then click on To
(or double click on the name)
Click on OK

Keep Method as Standard
Click on OK

Click on OK