I think the day of operation is wrong. 06613 has RSA with 06617. 06613 has a slot change, which affects the RSA pattern.
Earlier, 16617 arrives on Thursday morning, and leaves as 16613 at Thursday night.
The new specials, 06613 leaves CBE on Thursdays at 00:15, whereas 06617 arrives CBE on Thursdays at 06.30.