I did it got there at 10 no problem . They are very well prepared for that flight . On shabbos someone tells me oh your taking the chllul shabbos flight.
I took a Motzoei Shabbos ELAL flight, but that was in the winter. The experience kept me away from ELAL ever since, so the שאלה hasn't been an issue for me.
I don't know about taking it in the summer, I would suspect that it might be a problem, which is why I said one should ask LOR. That being said, causing צער to another Yid on Shabbos by making a statement about something that might happen on Motzoei Shabbos is also something to ask an LOR about.
The one time that I was advised on a summer Friday that I must leave on Motzoei Shabbos, DL happened to have been a better option (despite travel agent trying to push ELAL) so didn't have to ask. Since that flight also involved a מצוות עשה, I am not sure what the answer would have been if I would have asked about taking an ELAL flight two hours after Shabbos.