I finally collected the Acer Aspire ES1-131 with 8GB RAM extension on Saturday evening - and it's a nice little device, being so light and compact.
Then came yesterday and a bit of a faff installing McAfee. I'd actually been sold an extra year's extension to my existing protection, whereas I thought it was a new and different product - so it wouldn't install. But after contacting McAfee's excellent Indian-based customer support, they sorted it all out and all seems fine now.
Another Win10 update then followed - together with an alert that the machine was running low on memory...
Today I tried to install Office365, but couldn't do so as I didn't have enough free disk space. Huh? There's nothing saved on it yet... But I was able to get through to Currys PC World and they explained why. It seems that Dear Uncle Bill's Win10 updates save previous Windows versions to the C-drive, so as it was only 32 GB in the first place, it was almost full. They explained how to sort this - you click on the Start button, type 'clear' and that takes you to the disk clear up application, which calculates how much space you can gain. When it has opened, click again on 'clean up system files' and it'll do another scan. When the music stops, scroll down to 'old windows versions' or something like that - tick the box and delete. That gained me nearly 10 GB of disk space, so I was then able to download and install Office365...and yet more Win10 updates.
Currys PC World have been very polite and helpful throughout - and it's great to have a lightweight back-up computer again!