£5 off before jan 31st confusion

Last week I went to my first meeting and saw that some noobs had vouchers that said £5 off or half membership.
I told them i left my voucher at home. Thing is I don't one really and have been looking everywhere for one. On the website it says save £5 when you join before end of Jan and in this months mag but no voucher so now I am confused.
Any ideas where I can get a voucher or shall I just print off the front page of the sw website?
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