I'd love for it to be sooner, but I think we are looking at at least 15-20 more years. I think the timeline Musk has suggested is way too optimistic. There are a lot of hurdles to get over both technologically and with government regulations. I doubt the US government would allow people to go there without either a way to get them back or guarantees that they could keep a colony alive indefinitely. They'd need to send a whole bunch of equipment there ahead of the astronauts. Even picking and training the astronauts is way more difficult than with other missions because of the extreme long-term isolation.