Are you raising the old-fashioned cream ones - or coloured?

You'd have to wait until the bulbs plump up - at least a year - before you could expect flowers, in my experience. Leave them to grow on in the starting mix for as long as possible. Give them an uninterrupted growing time, rather than transplanting and disturbing those long tap root structures they produce.

Personally I'd use a coarse sand and leaf mold mix and barely cover the seeds. If you plant when the seeds are fresh and hold them over the summer they'll probably start in autumn when the weather turns cooler - which is what they do naturally. In this zone Freesias are putting up leaves from (southern) April-June. Right now they're coming into flower - and the temperatures are ranging from one or two degrees of frost to a dazzling(!) 11C. You'll need to factor in that 'cool time', I think. Not 'fridge', but definitely a cool spell.

Sounds like an interesting challenge.