We are travelling from Tirano to St Moritz on the Bernina Express, staying in St Moritz for two nights then joining the Glacier Express to Zermatt. I am having difficulty booking the luggage transport online and would very much appreciate advice if we really need to pre-book or can we just register our luggage at Tirano Station on the day of travel, then collect it at St Moritz, then register it for transport at St Moritz Station for collection at Zermatt Station. Thank you very much for any advice, PaulP