i can't see what is wrong with a designated space providing you take responsibility for it.
I had heard that one of the other Supermarket Groups had had complaints about refrigerated goods spoiling while waiting to be picked up
Whose fault is that in your opinion. If you order frozen goods it is obvious that they need to be kept frozen unless you wish to use them.
I have my shopping delivered by Tesco and don't know about 'Designated Spaces'. I'm not even sure that Tesco offer this option. I'm a bit slow in getting to the door some days but having used the Home delivery service for several years now most of the drivers who come know me now and allow for this as well as bringing the boxes right into my kitchen to be unpacked.
Not just a matter of time, but simply not being able to get to the door, even if I am up and dressed, which is by no means a given.
The "designated place" (sorry I should have said "place " not "space" ) option is offered by most couriers, the only exception I know of is ParcelForce and I have an arrangement with my local driver. I get three or four paces a week, up to £1000 in value (a Surface Book for instance), including my main meals which are all frozen.
I have a notice on the door anyway asking for deliveries to be left. This has worked for more than ten yeast, some drivers taking a photo of the notice and/or the goods. It has worked in the past with Sainsbury too but there seems to have been a change of policy.
People in this situation have my sympathy but I still don't have an answer for them apart from the obvious one of take your business elsewhere. Perhaps if you could get hold of the most senior executive and get a letter to him personally