No, sorry, my use of the word 'date' was probably confusing. It's the first lunch with Holly, the same one you're talking about where you have do decide between Alison and Holly. If you go with Holly, there's an exchange where Holly notices Lena, and says 'She's so pretty'.
At this point you have a choice as Ian. If you chose 'Yes she is', holly_change gets +1 towards wanting to be more like Lena.
The conversation from there is the same, with Ian commenting that Lena also enjoys literature. But it's noteworthy, because although Holly notices that Lena is attractive, the mechanic for her to want to change is only activated if it's reinforced by Ian.
The next time holly_change is modified is by Ivy and Lena at the sex shop.