Simulation Directives Changes Not Being Honoured

Hello All,
I am trying to add a simulation directive directly on the sheet like this:
.tran 1u 5u

And invoke the simulator, everything works as expected.
However, if I change the directive to:
.tran 1u 400u
and save the eeschema.

the simulation still stops at 5u.

It looks like the only way to make it honour the new change in the directive is to close the simulation window and restart it.

Is this the way to use it, or am I missing some step that ignores changes in the schematic?

Thanks.