Thanks for all your advices.
I almost made up my mind to continue shooting with my 40D for the time being for stills. As for video, my dad will let me use his 5D MK III or ID IV(too heavy for me) if necessary - for school and community projects.
He has 7 L lenses now - 24 1.4L II, 50 1.2L. 85 1.2L. one TS, 2 zoom lenses and a huge 300 2.8 and has recently acquired a Sigma 35 1.4 and a Samyang 35 1.4( same range and seems weird to me but he has the spare money to spend).
I will definitely go for FF and buy a refurbished or lightly used 6D in a year's time.