Hi Robert

     Contract module is the option that can solve your problem, you can tie entitlements with the contract module and the contract module can be set up to send a warning for you, in our case, we start to review our renewal with 120 day before to expire, and you can create a Dashboard to track the contracts when reach 120, 90,60,30 days before to expire.

  Due entitlements and Contract are tied, its very easy to know the contact information from the Entitlements and its easy to see which assets are covered by the contracts too, in contract module you can define the product owner and who need to approve the renewal and when using Contract Task sending an email to the approver keeping the approval history.

in my experience is a good module to control and track the renewals no matter if its Software or Hardware.

I hope this info can help

Regards