`x = 139, y = 141, rule = Langtons-Ant`

2$5.3A3.A2.2A$6.A3.2A.2A.A$7.3A3.A2.2A$8.A3.2A.2A.A$9.3A3.A2.2A$10.A

3.2A.2A.A$11.3A3.A2.2A$12.A3.2A.2A.A$13.3A3.A2.2A$14.A3.2A.2A.A$15.3A

3.A2.2A$16.A3.2A.2A.A$17.3A3.A2.2A$18.A3.2A.2A.A$19.3A3.A2.6A$20.A3.

2A.2A2.2A.3A$12.2A2.2A3.A.A6.3A4.A2.2A$11.A.A2.A.A7.A.A3.2A.A6.3A$10.

A.6A.A3.A2.6A.A3.2A.A2.3A$9.A.A.A.A.A2.A2.2A.A.A4.4A.A.3A.A.A$9.A.A4.

2A.A2.A.A2.3A2.2A.2A.4A.4A$10.A2.A.5A3.2A.9A.3A2.A.A.A$10.A.3A2.2A.A.

4A3.A2.2A2.3A.6A.A$9.A3.6A3.A4.2A2.A.A2.2A.2A.A2.3A$9.A5.3A2.4A2.2A.

4A2.3A.2A.2A2.A$10.A8.2A.2A2.A.A3.3A3.5A.A$11.3A2.3A3.2A2.2A2.A.A2.A

6.A3.2A$14.A.A.A.3A4.2A3.A.A.A.A.A.3A2.2A$15.A4.A3.A.A.A.2A2.A2.A.2A

3.4A.A$16.A.A2.3A2.2A2.2A.A3.A2.A2.A5.A$16.2A4.A.5A.3A.A.3A.A.2A.A2.A

$15.2A3.2A2.A.2A2.3A2.A7.2A.A$15.4A5.A6.A.3A3.3A.A2.A$15.4A3.2A.4A.2A

.A.2A.A3.5A.A$15.2A.3A.A2.4A.A.2A.3A3.2A.A2.3A$16.A.A7.3A2.2A2.A2.3A

4.A2.2A$16.A5.A.2A.A3.A3.A.2A2.A.2A.2A$15.A3.2A.A3.A3.A2.4A2.2A.A.A3.

A.A$14.7A3.A.A3.2A2.2A2.2A5.A.4A$14.A2.A.A.2A2.A.2A2.A.2A.2A.A.A.A2.A

2.A$19.A.A2.6A.4A.A.E4.A2.A$16.3A.7A3.3A2.A4.3A2.4A.A$16.A2.A2.A3.2A

2.3A.2A.A2.2A.3A.4A$16.A.A.A2.A2.A.A3.A7.2A2.4A.A$18.2A3.A3.A.2A.A.4A

2.A6.2A$16.A6.A.2A.2A2.A2.3A2.A.2A.A$17.A2.A4.5A7.2A.A.A.2A.A$18.A2.A

3.A.A.A.A.A.A2.A2.A.A.3A$19.2A4.A3.2A2.A.A5.A.A.2A.A$25.2A.2A2.2A.A2.

5A.A.2A.A$24.A.A2.4A.A5.2A2.3A2.2A$23.A2.A.2A.A4.A.A.6A2.2A.A$23.A.2A

.2A6.A2.6A2.2A2.2A$24.2A4.A4.A4.2A.4A.A.2A.A$25.2A4.4A9.2A3.2A2.2A3.

2A$45.A2.A.A.2A.A3.2A$46.2A3.2A2.2A$47.A2.A.A.2A.5A$48.2A3.2A2.2A.2A$

49.A2.A.A.2A.3A$50.2A3.2A2.A2.A$51.A2.A.A.A.A.A$52.2A3.2A2.2A$53.A2.A

.A.2A.A$54.2A3.2A2.2A$55.A2.A.A.2A.A$56.2A3.2A2.2A$57.A2.A.A.2A.A$58.

2A3.2A2.2A$59.A2.A.A.2A.A6.2A2.6A$60.2A3.2A2.2A4.A2.2A6.A$61.A2.A.A.

2A.A2.A12.A$62.2A3.2A2.2A.A5.A2.A3.A$63.A2.A.A.2A.A2.A3.A.3A.A$64.2A

3.2A2.A.A3.A.A.A2.A$65.A2.A.A.A.A2.3A4.A.A$66.2A3.3A.5A3.A.A$67.A2.A

7.A2.2A2.A$68.2A2.2A.2A2.3A4.A$69.A3.A4.A.2A4.A$70.A2.3A3.A.A.A.A$71.

A3.A2.A.A.2A30.6A2.2A$70.A6.A2.4A29.A8.3A$70.2A2.6A2.A2.A26.3A.3A.2A.

A.A$70.A.A2.A3.A.3A2.3A21.3A.A2.A2.2A.A.4A$69.A2.3A.A.2A.A6.2A.2A9.4A

3.A2.A.A2.A.A8.A$68.A3.A2.2A2.3A.2A2.3A2.2A7.A4.A3.A2.A.A.A4.A.2A2.A$

68.A2.A.A.A.A3.2A4.A.A.2A.A5.3A4.A2.2A.5A.6A3.A$68.A2.A2.3A2.A.4A2.3A

4.A5.3A5.A.4A.2A.2A2.2A4.A$68.A2.A4.A.3A.A.A2.2A.4A4.2A2.2A.A6.A4.4A.

2A4.A$69.A2.2A3.A2.4A2.A.A8.A.3A2.A3.2A.A2.A3.A3.A4.A$70.2A.A7.4A.A.A

.A2.2A.A.4A.A2.3A2.3A3.3A.A2.2A.A$69.2A3.A.5A2.A.2A.2A2.A.2A.3A2.A.3A

3.A2.2A4.3A.A2.A.A$69.2A4.2A2.2A3.A2.2A.7A3.4A3.2A.A.A.3A.A.2A.A.A2.A

$63.6A7.A2.A.A4.3A.2A.3A.2A.3A2.7A.A3.A3.A2.2A.A$62.A3.A2.A.A2.2A3.8A

5.2A.A.4A5.2A2.2A3.4A4.5A$63.A.A4.A.A2.2A3.2A3.A.3A.A2.4A2.A6.2A7.A.A

.A.A2.A.A$61.3A5.A.A.3A.3A.3A.A2.A2.A.A2.A.3A2.4A.3A.A.A2.A5.A.2A$59.

6A.A.A3.6A.2A2.7A6.3A6.5A.3A2.2A2.5A.A$58.A2.A.A3.5A5.4A.A.A2.2A3.3A.

A3.2A7.4A.A3.2A3.A.2A$57.3A2.2A.A2.A3.3A4.2A11.3A.3A2.2A2.A2.A.4A.A2.

2A.6A$57.3A2.4A.2A.7A.2A.A.A3.3A2.2A.3A3.A.2A.A.A.2A.A.A2.A2.A2.A.A$

58.A.2A4.A2.A2.A.2A.2A.3A.A.A.3A.3A2.A7.3A2.A2.A.3A.2A.2A.A$58.A4.6A.

2A.A.6A4.A8.A.A.A5.A2.4A.A2.3A2.2A3.A$57.A3.A3.2A.2A2.A.2A2.A4.2A3.2A

.2A.2A.A.4A.2A.A2.4A4.3A.A2.A$57.A.A.2A4.2A.A2.A5.A.A4.2A.A3.A.A2.A.

2A.A.2A.A.2A.2A.2A.A2.A.A$58.A.A3.A.2A.2A2.A.5A2.A2.A2.A2.A.A3.A.A3.A

3.A.A2.2A.A3.A2.2A$60.A2.A.2A.A3.3A2.A4.2A2.A.A.4A.A.A.A3.5A5.2A4.A.

2A$60.2A5.2A.A.A2.A2.A.5A.A2.A.2A2.2A3.A2.A.A.2A.A.3A.3A.2A.A$62.2A.

2A5.A4.2A2.A3.A.A2.A3.A.2A2.6A.A.4A.A5.A2.A$59.6A2.3A3.A.2A.2A3.A.A.A

2.A.A2.2A4.3A.A3.3A2.6A2.A$61.A9.2A.3A3.3A3.A3.A.A2.A2.A.3A.A.2A4.A8.

A$60.A.5A4.A.A2.A3.2A2.4A.2A2.A2.2A3.2A2.A2.A4.A6.A$60.5A2.7A.2A5.A2.

A2.8A3.4A.A2.A2.A8.A$60.A4.A.A.2A3.A.3A2.A2.3A5.A.A.14A8.A$58.A2.3A3.

2A4.2A6.4A.5A2.4A5.A3.A10.A$57.A3.A2.3A.5A2.A4.2A.4A.A5.A.3A.A3.2A8.

3A$57.A2.A.2A.3A2.IA2.2A.A3.3A.2A.A3.A3.4A6.A6.A$57.A3.A.2A.A4.2A3.A.

A4.A3.A.3A2.2A2.A3.A4.A4.A$57.A.2A.2A3.3A.A.2A2.A.A3.A.2A.A.2A.2A5.A

7.4A$58.2A2.A.5A.A.A.A2.A2.A3.2A2.A.4A.3A2.2A.A$59.A.A.3A.A2.2A.A2.A

4.A3.2A2.4A.A4.A2.A$60.2A.2A7.4A6.A7.2A.A6.2A$61.2A7.A2.3A7.A8.A$61.

3A3.A.A.5A8.A4.3A$61.3A3.A4.A.A10.A2.A$62.4A20.2A$62.A.A.A.2A2.A$61.A

2.A2.2A4.2A$61.A2.2A2.A.2A$61.A3.3A2.5A.A$60.A3.A.A2.2A3.3A$60.A2.7A

2.A2.A$61.A2.A4.2A2.2A$62.2A!

I found this while scribbling in Golly.

Notice the top left art (used to be a highway) is cut off.

This pattern has period ~90856.

I thought there were no oscillators in Langton's Ant?

It is only known that the ant's trajectory is always unbounded regardless of the initial configuration[4] – this is known as the Cohen–Kung theorem.[5]