If you OOC and there is a new batch starting soon, I guess they can just make u a lobo for a while then immediately join the next batch. That way you remain as REC till your BMT is over.
But in cases where the next batch is some time to go, it would be a waste of time as far as SAF is concerned, to let you lobo all the way. So they post you to some unit first, usually as a non-combat vocation since you are technically not even trained to fire a rifle. Most OOC people I know were either mechanics or store men.
And the irony is we finished our mechanic or store man training even before we finished BMT i.e. we became full fledged mechanics and store men before we POP.

In our case we went for re-course only when we were 6 months away from ORD. Still thought could escape. LOL
And being unit, as opposed to BMTC, the estab is such that there are no recruits. Lowest rank is PTE. And it would be lame to make you a Local PTE, so just make you PTE lah. Then when its time to recourse you get sent back to BMTC.
Dunno about now when the ranks can be easily removed, but during my time the ranks were sewn on so we kept our rank insignias. And we were addressed as trainees not recruits. I still remember during our last book out, we all agreed to bring in our respective units' berets during book in.
Was quite hilarious on the last day seeing an entire company of "recruits" who had ranks ranging from PFC to 3SG with different colour berets. Some even had RSAF and RSN berets.

I still remember our neighbouring coy just had a new intake of recruits, hair not even shaved yet.
All were staring at us with big eyes, probably wondering why these "recruits" so special, got rank and beret some more.