Flows not restored after mininet restarts

So here is my observations:

1) Controller OF10 plugin with AD-SAL FRM:

After switch restarts, flows are recovered if they have no idle or hard timeout configured

2) New OF plugin with AD-SAL FRM:

If I use mininet OF10, flows are recovered regardless of any timeout as long as the downtime is shorter than 1-2 sec
If I use mininet OF13, flows do not recover in general, I have seen 1 or 2 times out of many attempts.

3) New OF plugin with MD-SAL FRM:

Either with mininet OF10 or mininet OF13, flows do not recover after switch restart

BR/Luis