I returned 'full-time' at the end of Aug. I'm currently taking 5 weeks holiday, and then I'll reduce my hours to part-time when I actually physically return. So my holiday will be pro rated based on 24hrs from Oct to Dec, rather than August. My 5 weeks holiday will be paid in full this month.
They should be accrued based on the hours you were on previously for the time you've been off. I'm going back 4 days having worked 5 but I've still got my years worth of annual leave + 6 bank holiday days to use 😊 (our holiday is Jan to Dec) x
You get the holiday entitlement pro rated. So I work 80% (4 days a week) and get 80% of my full time holiday allowance. Bank holidays are weird and you're only entitled to 80% of those too but I tend to just ignore that and no one in my company has noticed or asked me to use my annual leave to cover it.