I do not think that you will part ways with Sophia / Elli or Sophia / Dylan now. This is not (yet) necessary at this point in time. It will probably be like the Alyssa / Elli election. (If you choose Alyssa you just have less Elli content only.) Sophia's thoughts and feelings will be interesting if she just watches. This could actually influence the future course of the game. Also with the possibility of Sophia / Emma.
I don't know if we have more information on a Dylan/Ellie storyline, probably as you say it's not like Emma's route that ends Dylan/Sophia (according to the walkthrough) but it will have different content while Dylan/Sophia still goes on.
But still I wonder what are the conditions for having the 3 events, given that afaik so far Dylan/Ellie is not optional (there are no choices), the only thing is the FW route as I reported in the last message. Probably we will know better with this update or with the other event at noon PD 13 where some choices maybe will be left to the player.
He once gave a roadmap for AWAM, according to that, no tasks were on Saturdays and Sundays.
Also on a logical front it would make sense to give a break to it or else Sophia's corruption in this storyline will become totally disproportionate with the rest of the game.
Even blackmailers have the right to rest on weekends
On a different topic: we were saying that Andy and Cathy will ask Sophia and Liam to be the maid of honour/best man, well apparently it has happened already, I didn't pay attention to this short exchange.
Concerning the wedding there are left the bachelor(ette) parties to organize and/or the wedding reception, like they ask to use their house for the ceremony and/or the party after that. Assuming that they are going to get married in San Alejo, not their hometown (they are on vacation), I guess there won't be a lot of people attending.
Obviously it could be something else not related to the wedding as well (cannot have children etc)