Hi everyone!
I found a mistake in my code and now I receive notifications even after the restart. The problem was that I forgot to call .connect() on Task Handler.
taskHandler = new CommandBasedWSHumanTaskHandler(ksession);
...
...
//this call is a must to be able to receive notifications...
taskHandler.connect();
My apologies to everyone.
I’m now closing this thread as Answered.
Again, thanks everyone for your help and participating!
Vlad