Nothing comes up using the given model number.
Please check it.
Are you sure it is "PWD" and not PDW.

In any case you will have to check the drain line.
A common place for it to clog is where it attaches to the house plumbing.

I am not sure why it is making your cycles longer.
The fill level should not effect cycle times directly as it is not monitored.
What can make cycle times longer is the water temperature.
The unit does monitor this and will hold until a certain temperature is reached.
Perhaps the water in the unit is cool so it takes linger to reach that temperature.

Check in the vicinity of #328 the check valve before the drain pump. sometimes something lodges in the intake of the drain pump. If the pump is not running, the it may be jammed or bad, or even bad control.

It makes it easier, but it is not impossible to do with it installed...... Might put a shop vac on the drain hose and see if some suction will help.... If not, suck all the water out from the inside of the dishwasher, pull the cover off the drain in the bottom (like 2 1/4" screws) and suck the water out of the sump, this removes alot of water before messing with drain pump.