Yes, I have a black sex link that occasionally has laying issues where she'll not lay for a day or so - then will get all hunched up looking and mope about - and then lay as many as 3 eggs in 24 hours. Usually I'll find them dropped in the run and sometimes they'll be soft shelled. Once she does that, she's back to normal.
I have no clue why she does this but I understand that sex links and those breeds that are "super-layers" can be prone to laying issues. Oddly enough, the last two times this occurred I had recently made a change in their feed. One time went from fermented back to regular. The next time I simply purchased a different brand of pellet. Went back to the original feed in fermented form and she's not had any issues in months.
Sounds like your gal has a similar situation. Keep an eye on her. I figure that laying issues will eventually be the end of the gal of mine.