I’m a founder that went through Techstars, not YC so maybe not exactly similar but accelerators want you to wait to Demo Day to have any investor talks while VCs want to get in early. Much like experienced used goods resellers will attempt to pick through yard sales early - no competition leads to investor friendlier terms. So an investor telling YC candidates not to wait to have these conversations isn’t exactly news. (Question whether waiting makes sense, but these are the dynamics.)