Luke Pennell has left the club by mutual consent.
The defender made 10 appearances for the Stones after signing from Dagenham & Redbridge last summer.
Head of Football John Still said: “I know Penns wells, having brought him to Dagenham a few years ago.
“I also know what he’s capable of and this is one of those where it’s not worked out as either of us had hoped.
“I wish him nothing but success and he’s definitely one I’ll keep an eye on in the months and years to come.”