appeal withdrawal and asking for passport

[Wardlisting24]

hey all,

i'm in the midst of appeal process, and been given hearing date of 23/4/13. as i was deciding whether to abandon it, i called my local ukba number - given on my refusal letter, and spoke to them. the lady asked me not to book ticket but call them when i've made up my mind so that they can return my passport. to assure me she advised that i'd have 28 days to leave the country and not affect my immigration history once i abandon my appeal?

now what i didnt tell her is that i already booked my tickets for 8/4/13. i didnt tell her this only cause i don't want to be in a position where my passport is ready at the airport and i have to leave ASAP, as i still have a few personal matters to settle and 8th april works best for me.

the reason for this post is just to clarify the info i was given, that i really have 28 days to leave once i ask for passport and that it will not affect my immigration status and show me as an overstayer, as i hope to be back in the near future?

can someone help me some info if possible?