This maybe worth bearing in mind when making these sorts of purchases!

"Under the distance selling regulations, the goods must be delivered or the service carried out within the time period they have specified. If no time period is specified, then the statutory time limit is 30 days (unless you have agreed otherwise). If the supplier is unable to fulfil their obligations within 30 days, they must inform you before the end of the 30 day deadline. They may offer you an alternative date for delivery, but you are under no obligation to accept and are quite within your rights to ask for a full refund.
Traders must provide you with specific information in regard to their obligations and your rights before you confirm your order. This is called pre-contractual (or prior) information and is dealt with in the next section, along with information about invoking your cooling off rights, returns, refunds and replacements.
Read more:
http://whatconsumer.co.uk/mail-order-goods-and-distance-selling/#ixzz4EtUdFUh4Follow us: @whatconsumer on Twitter | whatconsumer on Facebook "
I hope this helps.
But I have to say, I find the practise irksome in the extreme!

My regards, Bill