If you 110% sure it is HER on the forum cause she used her own name or some other identifying feature like her kids picture than I would definitely approach this directly head on verses being passive.
Something like 'not sure if you are aware but I am also on X forum and so imagine my surprise when I noticed your screen name with little Sally's photo as your avatar. I just wanted to say 'congratulations' as I had no idea you were planning on opening up your own program at the end of the month ~ that is going to be an awesome opportunity for Sally to be home with you.
So in the interest of being 'open' I will let you know I am putting up my own ads to fill her space since I am assuming the long term goal will be to have her with you and so I just wanted to confirm will X date be your last date as you indicated on the forum you are planning on opening for X date or were you hoping to leave Sally in my program a little longer until you got yourself up and running?'
If there is any doubt it is her than I would approach it passively from the 'hey you do not happen to be a member of the X forum do you?' and wait to see if there is a some horror in her eyes that she as been found out and give her that chance to do the RIGHT thing now that she has been caught?
I agree that honesty is always the best policy ... I have no issue helping out and supporting newbies to the industry and have resouces and links and so forth on my website for those considering it ~ there is a shortage of quality childcare in almost every region across Canada so why not support more people to consider this industry with eyes WIDE OPEN by providing information on what to consider before entering it ... I have even opened my program and allowed someone considering home childcare to spend a few days with me in the program to see the good the bad and the ugly of it to determine if it was something they truly could do ... so there would be no 'need' for anyone to not be open with me because I am very open about support myself .... however even with all the openness I have still had people who contacted me 'faking' being a potential client to try to get information from me and I agree it is in poor taste and when they are a provider themselves and have their HOPES RAISED by someone who is pretending to be a client maybe then they will understand that karma is repaying them for having done the same thing to others!
Treat people better than you want to be treated yourself and imagine the world we would create!

