buds with no fan leaves

well I am 6 week into flowering and my sativa is hurting bad. Nearly every fan leaf is curling, yellow and dying except maybe 2. My question is should I harvest if all fan leaves die or should I continue to let it grow (if it is) till the final weeks. The plant did receive 4 weeks of cold stress about 55 degrees at the beginning of flowering so is it just dying or what?

I'd keep it going, it will keep growing. It will probably grow slower, but it can still mature further without the fan leaves (I think the leaves on the buds can carry it till the end).