Here is update on activities/investments of HollyFrontier for its Tulsa Refineries (previous Sunoco & Sinclair Tulsa plants).
HollyFrontier seems have wrong focus point for its merged Tulsa refineries both were ~sweet crude refineries and only one had a coker (Sunoco). Prior to purchase & merger Sinclair was looking to add coker (drums were/are still Tulsa warehouse) and Sunoco was trying upgrade its undersized coker to handle more profitable sour crude. Holly is not going to be able to bring in any heavy Canadian Bitumen crude unless it upgrades its bottom processing whether they are connected or not.
Now that Enbridge has purchased & reversed COPs Seaway pipeline to take trapped Cushing crude and that is going to let WTI/Bakken/Canadian crude prices rise to real market value which puts pressure back on Midcontinent sweet crude refiners like HollyFrontier.
Regards