I have an ELCS planned in a few weeks and my mum is clamouring to know the date asap. I know it already, but if I tell her she will tell everyone else in the family including extended family, they will all be on my back, and she will pester us for the entire day by phone and text (I know we don't have to answer but then she will get hysterical thinking there's been a disaster and we'll never hear the end of it). She doesn't live near me and knows I don't want visitors for a few weeks around the birth, but she (and other family members) are not happy about it and basically want a ringside seat (which they are not going to get).
Last time DP let her know I was in labour and when I had an epidural and subsequent EMCS and kept her informed, we had her making shitey comments like how I hadn't learned to deal with the pain properly. (that is her idea of sympathy btw)
There's a chance the ELCS won't happen on the day as you can get bumped back by emergency ones - so it's not lying to say I don't know the date for sure.
Would I be evil to keep her in the dark and only announce the birth after? If you would do this, what would you say to her to keep it vague and not let her know without saying outright "I'm not telling you".