I got my earliest BFP with an FRER and a superdrug test at 9DPO. My latest was 17DPO, but that was my first, so i wasn't a poas addict like i am now! I tested with a cheapie at 13DPO and got a negative (but i looked for like a minute, didn't squint and didn't even get it back out of the bin!! lol!) then i didn't test again until 17DPO when i got a dark line.
My other two were 10DPO i think..