*POSSIBLE SPOILERS* When should I show my Husband the clip of the Ncuti regenerating?

This might be considered spoilers. I hope not because I could really use some advice. Try and avoid it be considered spoilers, I will be as vague as I can.

So I just introduced to Series 1 with Christopher Eccleston yesterday and he has FALLEN HEAD OVER HEELS for the show. He just found out that Christopher only has 1 series and we were talking about the regenerations. And I happened to say "I know that you are going to be floored by who the 16th Doctor is.". This has sent him on an autistic spiral into thinking about who the 16th Doctor is. I haven't told him who appeared after Ncuti's regeneration and I definitely haven't shown him. I'm just wondering when I should. I would really appreciate any advice on when I should show him. Should I wait to get to Ncuti's end before showing him? Should I show him earlier? I would love any advice you guys can give, thank you ❤️