The SMS service has limitations around the size of a message that can be sent. SMS messages have a maximum length of 160 characters. This is an industry standard, bookitlive does not have any control over the character limitation of a SMS.
Large messages can still be sent via the SMS service without having to manually break them up into smaller messages. When the recipient receives a large message it is sent as several individual messages. Once all parts of the large message have been delivered, the original, longer message is joined back together on the recipient's smartphone as one message. On older mobile phone the large message will be received as multiple messages.
When a SMS notification is sent by bookitlive it is split into 160 character messages with each message consuming 1 SMS credit. For example if your message is 350 characters it will be split into 3 messages and will consume 3 credits. When the message arrives is joined back together and appears as one message on a smartphone.
As bookitlive uses variables in the SMS notification templates the size of the message varies based on the variable information. For example a recipient' with a long name such as Alistair will use more characters than a message sent to Sam.