One pitcher may not sag enough but when you have a high flow day and the main is 50-60% full that may be different. Personally I would have stayed with the 3/16 all of the way for what I think you are describing. The beauty of 3/16 is that sap does not allow the gases to pass and thus, as long as there is pull (vacuum) on the line the sap flows.
Dave Klish, I recently ordered a 2x6 wood fired evaporator from A&A Sheet Metal which I will be converting to oil fired
Now have solar, 2x6 finish pan, 5 bank 7x7 filter press, large water jacketed bottler, and tankless water heater.
Recently bought another Gingerich RO, this one was a 125, but a second membrane was added thus is a 250, like I had.
After running a 2x3, a 2x6, 3x8 tapping from 79 taps up to 1320 all woodfired, now I'm going to a 2x6 oil fired and a 200-425 taps.