I've curbed leisure purchases on DL. I normally would have bought some leisure commuting RDU-ORD for May and June, and a couple of long weekends (SAT AM to TUE PM trips) over the summer. Instead I'm waiting to see what Q2/Q3 work travel looks like with potential client disruptions, and buying RDU-MDW commuting on WN towards my A-List. My last DL purchase is for the first week of April, and if I didn't fly another DL revenue segment after that I would end up at Silver.
Not much that DL can do right now, if work travel craters I will give up my DL Plat for a while and wait to use my 4 RUC for confirmable transcons in 2020. I would want DL to be generous with reclaim challenges if this lasts within the US into Q3 or later.