Some ligands are really fast. As for the alternating just before checkpoint, that's normal. The program seeks the lowest / best docking energy. If it's not happy with the first pass, it retreats and tries again until it either finds a minimum threshold or gives up, then moves on to the next docking position.

PS, your image is way too wide for this (ancient) forum software, it can deal with 600 pixels wide. No auto shrink.

I've seen several WUs that run to 50% in 10 minutes and then take a long time till 100%, ending up running somewhere between 3 and 3 and half hours, which is the normal runtime on my computer.

Seems like normal behaviour, work units are validated correctly.

Generally what you're seeing in this case is that the work unit you were given was a combination of multiple ligands (probably 2 since it got to 50% quickly). We estimate the runtime needed for each ligand. For this work unit, you may have been given a really small ligand which is really quick. Then got paired with a more difficult ligand that could take upwards of 12 hours. We split the second ligand so that it would finish the current work unit around 3 hours. The way the percentages work on the progress bar is based on ligands and number of runs in a given ligand. Which is why you saw it at 50% quickly.

Thanks,
-Uplinger

Why worry if the standard deadline is 7 days. Those that run devices with days of buffered work and know their's tasks can take 3 days (Android probably), might consider to go into the device profile > profile> custom profile radio button and limit OPN1 near the bottom to equal the number of active BOINC threads. My phone computes 1 at the time, so I've set the profile to 1. When the result is returned a fresh one is fetched with again full 7 day deadline. Even when it's a repair job it gets 3.5 days to work it out. More than enough.