Proof bump when using a thumper

[MooseMan]

Today I ran only my second run using a thumper, and have a question for those who use them regularly.

On both of my brandy runs with a thumper, I've had almost the entire run at 80-84abv, with evidence of tails coming in the high 60's-70's.
First run I charged the thumper with apples and water, second one, wine and fruit syrup.
I love the thumper for it's ability to boost flavours but the proof bump is not something I really want, as I don't want to age product at nearly 80abv or have to immediately add water to my product for aging.

So, what techniques do you guys regularly employ in order to keep the proof at a level that suits you on a spirit run?