I was in Bayonne a couple of days ago, and noticed that the train line to St Jean is currently blocked by landslip caused by heavy rainfall 'until further notice'. Substitute bus with revised times
http://www.ter-sncf.com/Regions/aquitaine/Fr/Etat_du_trafic/Default.aspx
http://www.ter-sncf.com/Regions/aquitaine/Fr/Etat_du_trafic/Default.aspx