I usually try not to fool with friction parameters to find convergence. Instead, I work with nonconverging nonlinear restraints (+Ys or Guides with gaps) by making them linear (Ys or Guides with no gap, respectively). It's easier to evaluate the output for these points.
By making +Ys into Ys, will that have an impact on running a hot sustained case as it may change the results of the temperature only load case?
I am still getting my head around the hot sustained load cases so apologies if this is a stupid question.