change·over 
/ˈtʃeɪnʤˌoʊvɚ/ noun
plural change·overs /ˈtʃeɪnʤˌoʊvɚ/ noun [count] : a change from one condition, system, method, etc., to another
▪ Were there any problems during the changeover from the franc to the euro? — see also change over at 1change
▪ Were there any problems during the changeover from the franc to the euro? — see also change over at 1change
