Do the big firms take future trainees on early if you ask ?

Hi guys,
I’m finished my FE1s and I’m starting my tc at a bigger corporate law firm in Dublin in April 2027. I asked them if they would have any ability to take me on as a pre trainee in September . Has anyone been taken on early like that before as I’m not in terms of starting their tc but has their firm been able to employ them as a legal exec etc before their start date ?

Thanks.