Will past ignorance come to haunt me? How long do I-Banks keep resumes on file?

Coming from a European country with no tradition in investment banking, studying domestically an irrelevant subject (Engineering) at an unknown uni to investment bankers (even though it is top 100 in Engineering globally) and with minimal experience and a poorly made resume, a few years ago I decided to apply online to numerous London summer positions of EBs and one or two BBs (think Citi/Barclays/CS/UBS). Of course I was rejected almost instantly. I improved my grades, I took 2 internships (commercial banking and engineering project management), I graduated in the top 20% of my class and I am about to work at a Big 4 in an off-cycle CF internship starting next month. I also took the GMAT and I have great chances of getting to a top European B-School for an MSc Fin by 2020 and finally pursue my career at an international hub like London. However, I always fear that I will be blacklisted from the embarrassing application I submitted back then if the firms I applied to actually keep the resumes on file. So guys, do you know how long do banks tend to keep resumes on their servers? Do they ever look at those or the positions you have applied in the past? I would love to have the chance to apply there again and be able to compete for a position.TL;DR: How long do banks keep resumes on their database and do they consider past CVs uploaded and saved on future applications?