Ncl future cruise credit question

[Orleanscruiser]

Can someone explain the following conditon from Norwegian's CruiseNext Certificate Deposits Terms & Conditions for US and Canada

 

1. When you purchase a CruiseNext Deposit, your shipboard account will be charged in USD and you will receive an instant shipboard credit towards your current cruise. You will receive the CruiseNext Deposit in the currency your current cruise reservation was purchased under (credit will go in your Norwegian Cruise Line guest record or Norwegian Cruise Line Latitudes account). Currency exchange rates are set at the time of purchase

[KeithJenner]

Whilst the certificate costs you $250 onboard (less the OBC you receive), you get a certificate valued in the currency for the country that you booked the cruise in. So, as I book my cruises through NCL UK my certificate is in pounds. If I chose to book through a European site then it would be in Euros.

 

The part that has been highlighted is basically saying that the conversion is done at the time you bought the certificate.