Lost Renders - Round Two

Anybody else having problems with rendering starting from the very beginning if the max time or max iterations is increased during the render - often simply opening the sidebar? I thought this issue was resolved, and my service ticket was closed just as it started happening every single time on the latest version of DS 4.9 (I just opened DIM to check for updates). It started out intermittent, then now happens every time.
Increasing time or iterations should have no effect on rendering like adjusting EV (which often doesn't create a restart), so this is puzzling.... Is it a bug or a shortcut in coding?