I think is impossible to happen to send bitcoin through offline or no internet connection because sending bitcoin is really need to connect to internet so the information will be updated . Maybe if you are sender of the bitcoin you really needed first the internet before you send but if you are the reciever even your offline is okay because once you reciever online using the internet the data will be update but all the time when you are using bitcoin internet is necessary.
Internet is very important nowadays, in order to make transactions we barely needed or it is necessary to have an internet to communicate from one to another. People are now commonly used internet connection not only because it is reliable but also it is an efficient way.