'Elective' c section

[New30]

If you had a planned c section when was it booked in? Do they run out of spaces for planned sections? Sorry if this is a silly question. Thanks in advance

I was given my date at 37+4 and was booked for 40+2 (breech) as there was no space in theatre before then, as it happens I went in to labour the following day so ended up with an emergency section.