As a SEO specialist, it's my responsibility to think about any possibilities of taking advantage of this page and if removing and redirecting it to a 404 will not cause me any damage.
The package that they no longer want to offer have been around for years, so most likely it already have page rank, it may already have ranked for a long time. They're not an e-commerce site by the way, they're a company offering services and have different packages for their services.
Like for example, they're offering SEO services, Web Design and Development, Social Media Management service, Pay Per Click, etc. They don't have a product but a package for each services.
So what did I do? I left it live, highlight the expiration date and have the "RELATED PRODUCTS" in the page to refer them other similar packages for the website visitors in case they landed on that page.
Did I make the right decision? Let's check out this video of Matt Cutts where Blind Five Year Old from San Francisco California asks:
How would Google recommend handling eCommerce products that are no longer available? (Does this change as the number of discontinued products outnumbers the active products?)
I think my decision was right, right? I don't want to redirect it on a 404 since the client said that they may renew the package any time in the future. To keep the page's authority on other ranked pages, I decided to keep it and at the same time suggest other services that the visitor may like.