Placement of y in a sentence using futur proche

Question

I thought there was a rule that "y" should come before the verb (including auxiliary verb).  There seems to be an exception when using the futur proche?  For example:  Je vais y reflechir rather than J'y vais reflechir.

Accepted Answer

Hi Andrew,
In the case of two verbs following each other (as in this case of 'futur proche' using aller + verb), the pronoun 'y' goes in between the verbs.
e.g. 
Je vais y aller = I am going to go there
Elle rêve d'y aller = She dreams of going there
Tu vas y penser = You're going to think about it 
Je demande à y aller le plus vite possible = I am asking to go there as soon as possible
Hope this helps!

Answer

Bonjour Andrew,
With the lesson here, «y» is replacing a group of words, i.e. a clause, etc. that begins with «à».  Here is the part of the lesson that explains this:
Note that the pronoun y can also replace a group introduced by the preposition à + [thing(s)]/[object(s)]/[location(s)] (but not a person), particularly with verbs that require à.  
In such cases, you cannot replace the noun alone with a pronoun, you must replace the whole à + [noun] group with y.
You are correct that y precedes the verb and it does in your sentence, it precedes the verb reflechir meaning the locuteur is going to reflect on something and that something is a phrase or group of words that begins with à.
J'espère que cela vous aiderait.
Bonne chance et bonne continuation.