I agree with Karen, I also suggest filing regulary (frequency to be determined) with complete e-mail chains to ensure TMF up to date and audit ready.
On the subject of e-mails, may I ask how e-mails are filed for an eTMF. Also how are attachments maintained? I understand for a paper TMF, e-mails may be printed and filed or saved on a USB, with this documented in the TMF plan.
It would be great to hear how e-mails are managed for an eTMF.