chromas to be included in the new blue essence store during Preseason.

Hello, I've been following the news about the merging of IP and blue essence that begins this preseason and noticed that it is stated that all chromas that have been available for 6 months will be available for purchase in the 'Blue Essence Store'. Assuming this refers to 6 months before Preseason begins (around November 7), I was wondering which patch would be the last one with chromas in the store? From what i can tell it seems like it would be either patch 7.6 or patch 7.9, or possibly patch 7.10. For clarity reasons, please try to phrase your answer inclusively, for example - "All chromas released on or before patch X will be in the store". Thank you.