If for example you are buying single tickets, e.g.Advance tickets to London for a one-way journey on a Monday, and Advance tickets for departing London on a Friday you will be able to use the vouchers during the Monday-Friday period, provided you show both outward and return tickets (remember to tell the train company staffs that you need to keep your outward tickets!
我查到官网上是这么说的,那是否意味着我不需要买return票
比如只要出示一下第一天进伦敦(比如从温莎),第七天出伦敦(去剑桥)的火车票
那么在这七天里都可以任意享受2for1?