PSW to Student - 4 months gap before ILR

Hello everyone. After briefly reading through some comments/replies to other people queries, I find this forum very helpful.

My current PSW visa will expire 8th August 2014. I am planning to switch to student visa. However, my ILR (10 years) is due in December 2014. I am in a full time (low skilled job). My employer cannot sponsor me, based on my job role. I have had a look around for other possible categories into which I can switch from a PSW....sadly only student visa came out on top.

My questions are:
1. I have asked to start part time job from October (term time), which my manager is still considering. I will apply for my ILR (based on the 28 days rule) on 16th December 2014. After I have sent off my ILR application, can I resume to full time work from January? Or would I still be bounded on my current visa regulations (i.e. student visa) until my ILR is issued (if successful)?

2. If for any reason I cannot continue with my course (as it is too expensive for something I do not want to do), and inform the university of my intentions to quit (after my ILR has been sent off), would I become an overstayer / illegal immigrant? And would this have any effect on the decision on my ILR?

thank you all for your help......much appreciated!

For Q1. its no until u got ur ILR u r bound to ur student visa work restriction.

Q2.Again once u hv received ur ILR u can withdraw from ur course but not whn ur application is under consedration as it would be a great risk.HO is quite quick these days n dey won't take long for ur ILR if its straight forward