Hi Resmura, I have just had this same experience - wanting to order the SIM to have it ready when I need it, but not start the contract immediately. Unfortunately, they advised me that they activated the SIM as it was shipped out from their warehouse, and that this is when the contract starts.
I don’t understand it because the SIM then still has to get to you in the post, so you’re paying even before you have any service, but I had a long online chat and that IS how it works.
Through the online chat they sorted something out for me (a small compromise), but my advice to you would be to wait until you are ready to start the contract before you place the order.
I asked the agent to pass on the feedback that the ordering process should be much more clear about when the contract starts, and there should be an option to start it at a later date, or when the SIM is registered in a phone.
Hope this helps, cheers,
Drew