Originally Posted by Globaliser

The email promoted the continuing availability of Avios on petrol via Tesco petrol stations. What didn't come out in vanilla8's post was the title of the email: "Get Avios when you refuel at Tesco petrol stations".

In that context, it would make perfect sense for this bonus to be available only to those who used to collect Avios on petrol via Shell petrol stations. It is to try to get them to switch to buying petrol at Tesco instead. The 40% bonus is a carrot for making the switch. The length of time for which the promotion runs reflects how much time it takes to change established patterns of behaviour for something like buying petrol. (I would have to go a long way out of my way to get to a Tesco petrol station, so there is a great deal of inertia involved. Which I shall probably not bother to try to overcome.)

So I think it's more likely to be purely wishful thinking that this 40% bonus applies to everyone for half of 2019.