recap Silence Of The Lamb p1 :
There was a lot of debate on the forums cool I want to read that about whether the parents should have switched the kids back, with a significant number of people under the impression that the error wasn't discovered until the kids were four.
well yeah they said the settlement was 1992 (kids born 1988) and when Mac said Why didn't they just switch us back? We would have gotten over it eventually?, V said "Suppose they had gotten pretty attached those first four years?"
so I think this must have been an oversight:
I hate to bring this up, but the first line of the story Veronica found reads "After [four or five, I couldn't really tell] years of legal battles..." So first off, the hospital didn't settle? As if. Second, that means that the parents knew about the error in short order after it happened. There was a lot of debate on the forums about whether the parents should have switched the kids back, with a significant number of people under the impression that the error wasn't discovered until the kids were four. Pretty eagle-eyed of me, considering that without contacts, my vision is 20/Holy shit, are you seriously that blind? heh.
I was held up slightly by the upcoming "you were switched w a baby born one day after you." bcs, wldn't their known birthdays be switched? the moms would know when they were in labor! so the girls grew up with the birthdays their moms remember as the day they gave birth, which was really to the other girl.
right? let's see if couchbaron addresses this.. nope (but maybe in the forums someone mentions it?):
recap Silence Of The p6: Mac asks if she's adopted, and says it would explain a lot if she were. Veronica lays out the baby-switching, and tells her that a girl born the day after she was went home with her real parents. Dawning horror on her face, Mac blurts, 'I was switched at birth...with [Makeup, Makeup, Makeup!] Madison Sinclair?'

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recap Silence Of The p8
Mac hands Veronica an invitation to M,M,M!'s party, and asks her to crash it with her. The invitation is in 09er code. Man, I want to marry the continuity editor.

so back on p1, he did indeed mean to blame the continuity (/timing) error on network execs *as distinct from* the show makers: Veronica references M,M,M!'s birthday as a "rite of fall," so put a tick mark on your scorecard under "Errors Of Continuity Caused By Candy-Assed Programming Executives." bcs this episode was delayed, so that it Aired on 2005.01.04 when had been planned to air before AEFC (and, I guess, before a December hiatus of several weeks)

Mac won't be deterred: "It's my chance to see how the other half lives, especially since I should have been the other half." Yeah, I feel really sorry for you. People as talented at web design as you are never make any money. & earlier cbaron commented to same effect when she pulled out a powerbook. that he d n know the expression was 'rich little poor girl.'
Party. Wallace is accompanying Mac and Veronica. M,M,M! opens the door, and the three of them are all festive in wishing her a happy birthday. Hee. M,M,M!, horrified, asks why they're there. Wallace: "I came to celebrate your birth, but these two just want to hook up."
Mac checks out pictures of the fam in Egypt. She goes into the study library, where she discovers a BRUNETTE younger sibling. Again, the casting director deserves a raise. Getting a brunette girl is one thing, but this girl is exactly like Mac.
Veronica pulls up to Mac's house, Mac in the passenger seat. Mac bitterly wonders if M,M,M! has read even five books in that massive, beautiful library. I doubt it. I don't think 1001 Ways To Be A Massively Made-Up Bitch comes in leather-bound hardback. Mac rants on that she has a blood sister she's never known, and wonders why her parents didn't trade them back: "We would have gotten over it eventually." Well, I've gotten over the seventh season of Buffy, but that doesn't mean airing it was the right thing to do. Veronica wryly speculates that the parents got a little attached. Well, the ones who had Mac, anywaygood point. Mac wonders why they didn't figure it out before then, and I refer you to the microfilm.