I've been badgering Class Charts for an update since 26 Jan, and they still haven't told me what their problem is, they offer no timeline, no escalation (why do they not have account managers?), they promise to get back to me with an update, then never do! I can't find a way to escalate the issue within TES either. I've asked for compensation as we're not able to reliably communicate with parents, but again they're not able to offer me anything!
Thankfully SLT have listened to me and other users in the school and they're happy for me to cancel the contract before next renewal, but that doesn't help me now!