Covering red paint

[Neenee]

Hi I need to cover pillar box red paint. I have an attic conversion with some sections of the walls being pillar box red colour. These part of the walls have about 4 coats of paint on them as they were newly plastered walls 5 years ago. My daughter now would like a colour change up there and is wanting what is called bright pink in the dulux or crown range. It's like a shocking bright pink colour. Would I need to prime the red walls prior to paintin the new colour To lift them? If so what colour primer would I need to use?

Any help greatly appreciated.

[albaqwerty]

I'd be tempted to paint the red with a cream or magnolia quite a few times to see what colour it showed and then make a decision if another coat was required.
(One of mine wanted Black skirting and coving)