Other than services 198, 506 and the current 160, Bt Batok have
never operated any of the Jurong East / Boon Lay services before.
All are operated by the old Jurong Bus Park followed by the new
Soon Lee multi-storey depot 
(If so, u would have seen more Striders and MK3s on services like
78, 79, 97, 98, 143, 183, JE feeders etc......
)
For your info, Kent Ridge services 151 and 200 were also once
operated by Jurong. It was later transferred over to Bt Batok /
Ayer Rajah somewhere in 1999 when CCK services were transferred
over to Tibs.