When using many accounts, i often get Invalid session (even after closing all MC and restarting PC)

Hello,

I got 14 accounts which i use everyday.

Playing on a big server, and are using 12 of them to load farms around them.

After the latest update (where quick play came), i have seen a rather annoying bug.

I use a laptop to run most of the alts (usually 9).

When i get "invalid session", i often close all mcs down, restart the pc and then open all 9 mc up again - connect to server and all is good.

Now i keep getting invalid session on 2-4 accounts, no matter what i do, i cant get them on.

I can restart the pc 5 times, open and close launcher, nothing helps.

If i log them in on 1 of my other pcs, they log right in.

 

Email "support" told me to open this bug.

How do i progress from here?