Hi Lucy,
No-one will be automatically transferred from DLA to PIP. At some stage you will receive a letter 'inviting' you to apply for PIP, you will have to request the forms yourself. As long as you do this, and return the completed forms, within the specified time-frame, your DLA will continue to be paid until 4 weeks after a decision is made on the PIP claim.
Initially we were told that everyone on indefinite DLA would be transferred between 2015 and 2017. However, the process does not seem to have started yet and it is possible that the time-scale could be changed depending on the results of this year's general election. I'm afraid that we all have to wait and see