Thank you all so much for your help! We are getting there. The input is short with stories, a video, ppt etc. I then set a task - they've been quite simple and structured (mainly to help out the parents). So far it seems to be working - we have to stay online throughout the morning to answer questions/ queries - I usually check back in on everyone at home each 1/2/ hour to see if they need any help or suggestions, making sure they take breaks, go play, do something practical. The afternoons I set a practical activity, exploration, play based learned, craft activity etc. but we are not online although available by email if the parents need me.
My worry is, I feel that it's not as reception should be, as my time is split so much. Free flow and play happens if the children are in school but having the time to observe, do focus work and ensure that the children are ok online, is difficult.