Sea Soldier is not likely.
Airforce probably.
YOU COULD be posted to Navy camps, but still under Army. Meaning you'll still do the Infantry Conversion Course during the last 2months before u ORD.
As for Airforce, probably 30%++ of you will be going to Airforce. If you're listed as BAF (If i remember correctly the term, I'm one batch before you), you'll be converted to Airforce Personnel. Meaning you'll no longer need to do Infantry Conversion course. IF you're listed as ACF, you have a chance to be posted to Airforce camp as army personnel, again you'll have to do infantry conversion course later on.
Trust me, you'll rather be in Army camps than Airforce/Navy camps. Airforce sucks(except for sembawang) cause there's a lack of manpower everyday. Do expect to do a minimum of 4 hours(up to 7 hours) of duty EACH SLOT, and up to 3 slots per 24 hour shift. 2 hours shift 4 hours rest is non existent.
Although the Infantry Conversion Course may sound shitty to you, at least you'll enjoy your 1 year 4months of 8am-5pm and bookout (Assuming you're Army and not posted to Clementi Camp).