As nobody is interested to solve this problem, I found WA for this. Manualy edit dashboard’s json and save. In json there are two sections “current” and “options” keeping different values. I don’t know it’s meaning for grafana engine, but modifying it to the same value in both sections - solves problem. It looks like grafana uses “current” value but saves new value in “options” section. I addresed this in Two different variable values in json (current vs selected) - but got no anwer.
BR
Mike