[Deb Mac]

Seems that way on mine as well. I'm not in front of it right now, but since that drain sits in front of everything else, including accessing the pump, I'm pretty sure it's in front of the heater plumbing as well. Since I want to reputty the sink strainer, I'll be disconnecting the drain pipe at some point anyway, so I might as well disconnect it at the sink and the trap and that will give me better access.
I'm pretty confident in the ability of the general plumbing to empty via the low-point drains. But I can hear water gurgling in the pump head, so that is my main concern. I'll just pull a couple of litres of pink through the pump and flush the toilet - PO put an aqua magic IV in there (no black tank, whole other project for spring - poor man's Sealand), so I need to make sure I have pink in that. Don't need the toilet to crack a line! I'll deal with the water heater by-pass next season.