I am a huge proponent of senior postdocs applying for the K99 pathway to independence award (regardless of whether it is ultimately awarded). This is mainly because I think so many aspects of the application are necessary for networking, independence and vetting a research proposal you can recycle at job search time. If you apply for the K99 twice, you get a minimum of six reviewers to provide feedback on your proposal. Getting that many people to read anything you’ve written is generally quite a stretch, so this is a huge advantage. When it then comes time to apply for an independent position, it makes sense to turn this proposal into your job application research plan.
Those final postdoc years are also extremely busy: publishing the last big paper (which includes doing difficult reviewer-requested experiments), going on the lecture circuit to promote that last big paper, networking at conferences, preparing job application materials, and then … more networking. That excludes the enormously time consuming activity that is the actual application process itself. All of this is compounded if you are on the job market for more than one year and you only have a handful of short months to improve your application/publication record for the next round. The overwhelming temptation during this busy time is to see that you had put a lot of thought when you were less busy into carefully preparing a K99 proposal. Again, more importantly, you had gotten a huge amount of feedback on that proposal. The natural inclination (and indeed recommendation by many) is to rework this document into a fresh research plan for job applications.
However, the window for eligibility for the K99 has shrunk in recent years to 48 months. Also, the K99 is a training grant. It requires that you make a case that further training is required (i.e. that your appearance on the job market is not imminent). If it is awarded, the K99 period must be no less than 1 year. With a deepening of the postdoc holding tank, it also takes more years for postdocs to become competitive for independent research positions. This leaves a gap of potentially >1-2 years between one’s final K99 submission and applying for an independent position. What’s true for myself and I suspect many others is that there is substantial intellectual maturity and evolution of your science that can happen in those 1-2 years. It is no longer clear to me that using that document from your mid-late postdoc self as a crutch when preparing your research plan is your best option for putting together the most sophisticated application.
My experience that led to this blog post: I did use my K99 proposals as the basis of my research plan. I got several great interviews from it. Shortly after starting my tenure track position, I quickly put together a grant application with no overlap from the K99-based research plan for an NSF proposal. My strong feeling is this de novo submission was an order of magnitude better than what my mid-postdoc self came up with and reworked for job applications. We’re all constantly learning and growing as scientists so it’s not uncommon to think that any grant we wrote a few years back is terrible.
I’m not suggesting anyone trash all their hard work from the K99 application. I do however recommend looking at all your most recent data with fresh eyes and considering the best way forward without feeling limited by your previously vetted proposals. For all those on the job market or on the job market again, best of luck and hang in there!