Truworths - Truworths exchange policy on 50% sale items

I made an online purchase for items that were on the extra 50% sale that Truworths offers. Apparently the extra 50% sale only runs for 4 days.
I received my online order, after 4 days because online orders take 7days or even more before you can receive them. One item was a pair of boots & the other one was a coat.
I went to the nearest branch to exchange the sizes on both items, I was told I'm not going to get the items at the price I bought them for because the 50% sale period has passed,it only lasted for 4 days.
The sales consultant confirmed that I will get the items at the original sale price and not the 50% sale price.
I find this unfair to the customers because first of all, online orders take 7-14 days to arrive at the store, secondly it is not mentioned anywhere in Truworths exchange policy that extra 50% sale items, bought online have to be exchanged while the sale is still running for customers to get them at that price.
The sales consultant gave me two options, first option was to continue processing the transaction at the original sale price and not the 50% sale price or to credit the items.
I opted for crediting the items because I was not happy with buying them at the original sale price whereas I got them at 50% sale price.
My concern here is the fact that there was no way I was going to receive my online order within 4 days, therefore it's impossible to exchange the items within 4 days.
Secondly, it is not written anywhere that 50% online purchases, will be charged at that price only if you exchange within that 4 day sale period.
I'd like to be contacted by someone to discuss this further.
Or drop me a mail on the address provided.
Thank you for bad service Truworths!