The centre-back joined The Shots in August 2017 following a successful trial.
A former England under-16 international, Lyons-Foster is a graduate of the Tottenham Hotspur and Aston Villa academies and joined Bristol City in June 2016.
Last December he enjoyed a month`s loan with Bostik League South outfit Guernsey FC and in February spent a period on trial with League of Ireland Premier side Derry City.