Wedding Date Clash

Hi All!! This is my first post and I’m looking for some advice on a potential wedding date clash…
We got engaged in November and have just started looking at planning/venues. Ideally we’d like to be married next year in 2025 (I’m aware it will be a lot of planning but we don’t really want to wait until 2026 as we want to try for a baby asap after the wedding)
There’s a venue we really like and are going to view this week. If we like it, they have late availability for a Saturday in May for £5k instead of £8.25k which is a huge saving for us, we’re also considering a Friday in November for the same price so to me the Saturday in May seems a no-brainer (apart from trying to plan a wedding in 6 months)We will also be looking at other venues with late availability but as we want to use an external catering company and the options for this seems so limited
My potential issue is I asked my bridesmaids to be if the May and November dates work for them and one came back saying it’s their Partners 30th birthday that date and they already have plans and will be on holiday.I spoke with our mutual friends and they think she would cancel their plans to come to the wedding if we did hold it on that date, but I still feel uneasy asking her to do this (even if not directly asking I am essentially asking her to do this). She’s one of my best friends and I can’t imagine her not being there. Any ideas please? Now I have the idea of a sunny May wedding, November just seems like a comprise which I don’t like for my wedding day x