x = 95, y = 35, rule = B3678/S34678
43b7o12boo4boo13boo3boo$65boo19bo$41b11o8b5obb5o9b5ob5o$39b4o7b4o4b4o
bb4obb4o5b4obb3obb4o$39b15o4b16o5b15o$38b5o7b5obb5obb4obb5o3b5obb3obb
5o$38boob11oboobboob5obb5oboo3boob5ob5oboo$65boo19bo$43b7o12boo4boo13b
oo3boo5$23booboo$bboo8bo3bo5bob3obo$6oboo5b5o4b5obo$11obb8obb6obo$b30o
$11obb8obb6obo$6oboo5b5o4b5obo$bboo8bo3bo5bob3obo$23booboo5$43b7o12boo
4boo13boo3boo$65boo19bo$38boob11oboobboob5obb5oboo3boob5ob5oboo$38b5o
7b5obb5obb4obb5o3b5obb3obb5o$39b15o4b16o5b15o$39b4o7b4o4b4obb4obb4o5b
4obb3obb4o$41b11o8b5obb5o9b5ob5o$65boo19bo$43b7o12boo4boo13boo3boo!

A period 8 gate which shifts the phase of rockets by 28 generations.
This uses six period 8 spark oscillators to shift the phase of a rocket
which passes through by 28 generations.  Since the gcd of 28 and 40 is 4,
using multiple of these gates in succession can shift the phase of a
rocket by any multiple of 4 generations.
