If you are managing the trade with a trend line, why use a trailing stop at all?
If you want secondary confirmation, perhaps use either an ATR or countback line trailing stop set so that it is at least below the trend line. Use the smallest value that doesn't show a stop-out during the trade so far, or possibly add a little extra, depending on how far below the current action that would be.
Here's JST with a 2xATR(14) stop at the top and Countback stop at the bottom (3 steps back covering 4 bars - one more than the Guppy standard). The ATR stop can actually go down to about 1.5xATR(14) before it stops out, but if I set the countback line to the standard 2 steps/3 bars, it stops out on the third-to-last bar.
Cheers,
GP