When does M&S usually run 20% off womenswear Sparks offers?

[MotherWol]

I'm in need of a few workwear items, and I've got an M&S gift card to use, does anyone know typically when they do the 20% off womenswear offers via Sparks?

Oh the jacket I wanted was sold out in my size in store and I mine so I ended up just picking up a pack of knickers- didn’t realise it was single use….. feel soooooooooo scammed M & S 😫😫😫

Same ! Annoyingly not everything i wanted was in stock online but i refused to do 2 transactions . Admittedly when this happened before ( single use voucher ) and I needed both online and instore I phoned customer services and they credited me with the 20% as wasn’t really my fault that all items weren’t available via 1 channel

I’ve just had this discount in sparks account today

I think it was something to do with some M&S anniversary so probably just a one off.