Use of "en" and "y" as replacements

Question

Hello,Can you help me understand the use of "en" and "y" as replacement pronouns in the sentence "J'en profiterai pour y aller avec lui"? I understand the general rules as explained in the lessons, but in this case I don't understand why they are both being applied. Wouldn't you just use "y" here to replace "la banque" ? Why are both "en" and "y" used? Thank you.

Accepted Answer

Indeed, this is a bit tricky. The simple explanation is to point out that there are lots and lots of idiomatic phrases around en and y. In this case, the phrase used is:
en profiter pour... -- to take the opportunity to...
If you want to dig a bit deeper, the verb profiter often implies the preposition de (profiter de qqc -- to enjoy something). And that kind of explains the presence of en. But it is often simpler just to accept the phrase as idiomatic and swallow it whole.
To see where the -y comes from, let's look at how the sentence might appear without y:
J'en profiterai pour aller au cinéma. -- I'll take the opportunity to go to the movies.
It is clear that y replaces au cinéma (or whatever destination was specified in the context).
J'en profiterai pour y aller. -- I'll take the opportunity to go there.