You have setup the offline according to step one of this 

recommended workflow in the wiki to the right

Graduate (881KA) MFA Documentary Double System AVID - Post Production Workflow

Now you are ready to "On-Line" or upconvert the footage to

a higher resolution

If you already deleted your linked files go to the source browser and

bring them back into AVID

Navigate to the linked footage and re-link

Or if they are still linked in the project open the linked bin

Next Hide the AVID Media by taking the 1 folder and moving it out of the MXF folder

Maybe change project probably

Next we need to relink to the higher res footage

Right click the timeline and choose >Relink

Footage re-transcoded to DNxHR HQ

Right Click the timeline and choose Re-Link