Yea but it might cross over to 222 instead. Seems random to me
lol :)
I don't think the BCs driving these 5 30e buses care so much
anyway, as long as the bus appears on 30e after doing extra trips
on either 222 or 229 can already. 
Anyway just want to point out, contrary to what Sgwiki states,
these 5 buses' (the 4 DM3500s & 6172Z) parent service should be
30e instead, not 222 or 229 respectively (unless something changed
recently that I'm not aware of). They just happen to X-over to
these services before and after they do their 30e trips during peak
hours. It's similar to how CT18 buses X-over to 225 (used to before
225 added DDs) and 228 during peak hours. But if i'm not wrong,
they do do more trips than what CT18 x-overs will do, that's why
they seemed like perm 222 instead as their parent service.
Many years back Sgwiki's statuses for the Sv 30e buses is (BN
30e/222), but idk which guy suddenly change it to (BN 222/30e)
instead sometime back, then suddenly everyone used the (BN 222/30e)
for cameo spottings. Just look at the 'Chinatown Direct' services
page on Sgwiki then compare with that of Sv 222 & 229 on wiki
as well, you will see a difference in describing the x-over
duties.