My company makes a product and due to circumstances that we've seen coming for months, it's going to stop working extremely soon. We've known it was coming, but didn't know the exact date. I'm technically supposed to be someone that works on new development, while also supporting this product, but the product has been stalled for years. The owner didn't want to invest in it and the original developers had an entire team of people. Now it's just me supporting the existing user base. This means I haven't been able to do any new development. Now that this crisis has occurred, I'm expected to be able to do new development to fix it.
The only old developer that still works there is in a new department now. I reach out to him occasionally on other topics, but he barely knows more than I do regarding this specific development. My boss ominously told me that "if we can't fix it, that product is finished". That would mean my entire purpose at the company is finished.
The only solution I can see is if the other developer and I are both able to give 100% of our time to it. Realistically that's not possible because we both have other tasks and neither of us actually knows the entire product because it has basically no documentation. I don't want to "abandon ship", but would just looking for a new job be a good use of a my time?