I think it depends on your personal, familial; and, of course, your financial situation. I too am expected to start graduate school in the fall, and while I am worried about the current crisis and coming economic fall-out, I have been saving money for a while now and don't have a family to care for.

If you have a wife/husband and kids to care for, I would very carefully consider whether now is the best time to make a commitment (both financially and time-wise) as big as graduate school. Conversely, if you are as passionate as you say about your field and furthering your education, sometimes the risk is worth it.

Its up to you in the end, but if you wany my opinions, I'd wait until the last possible minute to resign from your position and start looking NOW for RA jobs. Hell, schools may still be closed come September and then your decision becomes real easy (heaven forbid).

Cheers