Amending a booking

Flyingfox

We initially booked a site in July. Received a confirmation email, no problem there. We then decided that we could stay a day longer so I amended the booking by one day. On my profile it shows the amended booking but I have not received a confirming email which I thought that I would. Can I accept that the booking is confirmed without an email ? I always print of the email to take to the site as proof of booking whether I need to or not.