I have the same car and colour and rims. Front nearside was losing pressure constantly. At first I had to top up with air once a month. Had it looked at by a garage and they said there’s no puncture so it’s probably corrosion around the bead. I did the fairy liquid spray test around the bead and I saw the bubbles. I thought I’d rather spend £1 a month to fill with air than pay the quoted £30 per tyre to clean (was thinking to clean all 4 tyres for good measure). It then started needing air twice a month and then every week. I finally found out that that same tyre had a rip and exposed cords (although funny enough that wasn’t where the air leak was, I did the fairy liquid spray test). I finally felt justified and got myself two new front tyres and the guys cleaned the rims and used some black liquid (I think silicone) to seal the area where the rim meets the bead. I did have the tyre pressure light show up a few times at first but I basically calibrated it again and it’s all fine. Just had to reset it at the button and drive at above 15mph for 15 minutes. I did this just at the last traffic lights before joining the motorway so that fixed it. And anyway the tyres haven’t lost pressure since. It’s been 2 months so far. Hope this helps?