hi hamaflo,
some funders do exclude students who have already started. others exclude part-time students. but as far as i know, you can apply for full time funding for your second year while you are in your first year.
i definitely applied for funding from ESRC during my first year, for my second - though i was doing FT already. i know some others who didn't just apply, but did indeed get the funding for their 2nd-4th year. if you are thinking of particular funding bodies, you should check their guidelines, maybe call them up to ask.
i think you need to consider: a) what will you do if your applications aren't successful? b) why exactly do you want to start now - you could defer your place and maybe start a year later as a full-time, funded student right from the beginning.