illegal- may be not but against the spirit of the rule. If HO decides to check with you Bank then it may result in a rejection. 1 month window has been provided for applicants to arrange statements/letters from Bank etc. If you go by the spirit of the law/rule, you should have such funds available ...

I've been in the UK under the student visa (4yrs) then IGS (1 year). I have gathered enough earnings to apply for the HSMP. Unfortunately, at the end of my IGS, I was travelling outside the UK and only manage to re-enter UK one day after EXPIRY of my IGS, now as a tourist. Can I still apply for HSMP ...