For pupils with an EHCP, an early annual review must be called and you will need to contact the SENCO in the first instance to get this arranged. For pupils in year 6, all annual reviews will be completed in the first half of the Autumn term, irrespective of where they are in the annual review cycle.
You will either need to state the name of the school or the type of setting that you wish to apply for. This will then go to the local authority and the schools will be consulted with and a decision made. You may not get the school that you have asked for and there are numerous factors which can determine why a place might not be offered. While the law very much favours parental choice, it is not a cast iron guarantee.
It is worth noting that special schools within the borough are heavily oversubscribed and places are difficult (but not impossible) to get. Your EHCP case officer and the SENCO will work with you to try and advise. It is always worth visiting or speaking to a prospective school and we would encourage you to do this before a change of placement request is made. Movements to schools outside of Southend on Sea always need to go through the local authority SEN team as they will liaise with their counterparts in other local authorities.