How do you define this in terms of literature

Ill throw my two cents in!!

You have a reworked adage, the original as we all know is:

Early to bed
Early to rise
Is the way to be
Healthy, wealthy and wise.

An adage is like a proverb, a saying that has gained reputation to be true over time.

The re-working of the last two lines makes me think that it can be called a epigram which is a witty saying.

I think it could still be termed as an adage despite the substitution because who doesn't realise the proof that advertising works!!