It’s always 7-10 days (some people swear implant on day 4 or day 11 or 12 outliers). Which day it occurs on could change and we don’t know exactly which day you implant.

We are very thankful to have two healthy children after one IVF and one FET (and one miscarriage in between) but I’ve now done multiple FETs (4) with no success (and some pretty horrific stories of bleeding afterward, but that’s another story for another day!). Doctor has suggested a couple different things, including an ERA. But would/can implantation window change from my last successful cycles? It seems like it would be a constant or are you supposed to get a new ERA after every pregnancy?