Sybase has specifically not recommended doing this in the past. (There was a Sybase Tech Doc related to PFC incremental deployment, but I can't find it on the SAP site.) Particularly, incrementally deploying any PBDs containing any class objects (windows, user objects, menus) is risky, because internally, references to other objects (ancestors, PowerScript referenced objects, etc...) are encoded as offsets into P-Tables. If something you've done changes the sequence of a P-Table, things could get pretty messed up, and it will be next to impossible to diagnose. (Code will be executing that doesn't make sense looking at your source code.)
I've seen people advocating incrementally deploying PBLs/PBDs containing only DataWindows (not classes), but in the depths of my creative imagination, I can picture that practice breaking the app with an incremental deployment. (I'm picturing a DataWindow referencing a global function that is overloaded, although the method of overloading isn't documented or sanctioned by Sybase AFAIK... still....) OK, it's a pretty slim chance of risk, but I suspect it's not non-existent.
While saving bandwidth makes sense, unless the cost is pretty high (e.g. 500km from the nearest station in Antartica) compared to most major metropolitan markets, the cost savings might not be worth the risk. (I downloaded Windows 8.1 over a public WiFi access point last week. No biggie. I'd probably download your app while I took my coffee cup to the garbage. <grin>) There are plenty of good, user friendly file sharing services that can help you with that deployment.
Bandwidth is cheap. Reputation is priceless.
Good luck,
Terry.