As above - I don't think English teams get 17:45 slots when playing at home.
Neither Arsenal nor Man Utd had a single 17:45 home fixture this season:
https://www.90min.com/posts/europa-league-fixtures-results-2022-23-season
Even if they did offer three-match bundles AND every single season ticket holder took them up (they won't) there would still be match by match ticket availability.