I'll answer. I would say the most serious challenge is the gaps, because you're not able to predict. If you knew you weren't going to get funding at all, you would scale down your research and move on, I guess, but because there are gaps, you're always waiting for the next funding program.
You're not sure where to go when everything is put on hold for a bit. That makes it very difficult to try to build a long-term research program and to secure resources, both the physical resources, such as experimental greenhouse space, as well as resources of researchers. I would say that the gap and the lag in approval times is really the biggest issue we have.