Because Help to Buy: equity loan homes are generally on new developments (and may still be under construction), in common with most new home sales, you will be expected to sort your mortgage and they require you to exchange contracts within one month of paying your reservation fee.
Your moving in date may depend on the time required to complete construction work – this will vary from scheme to scheme. Some Help to Buy applicants may need to wait for a longer period for a home that matches very specific needs whereas others may buy from a development that allows you to move in earlier.