Dear Annemarie, Suprise Lilies can have more than the usual 6-8 blooms. As you know, blooms are set up based on available light, soil moisture and available nutrients in the soil. In a good situation, blooms will be larger and last longer. Since we are talking about the reproductive side of the plant, there can be things that happen that would allow the plant to create more flower buds.
Sincerely, Richard Hentschel