Mar 29, 2016 - 5:58 AM
Hi sosswood, welcome to MySwissAlps!
No worries, this can be solved easily. You are indeed too late to buy online, and the Swiss Transfer Ticket can not be purchased after arrival in Switzerland. However, I doubt if the Swiss Transfer Ticket would be your best option anyway. If you only travel to Montreux on your first day you would need a different pass. Other passes can be purchased at the rail station of Geneva Airport. The main disadvantage is that you may have to wait a while for the ticket office if it happens to be a busy time. So you might miss the first train, but you can buy a pass and take the next train.
Apart from any pass you will buy, trips close to Montreux will be free with the Montreux Riviera Card you will receive when you check in (myswissalps.com/montre ux/hotels) . So, no reason to stay put in Montreux. Have fun!